Julianatop, Suriname Highpoint

Julianatop, Suriname Highpoint

Eric Gilbertson, Serge Massad, Viri Alvarez, Fernando, Scott Beems, Dean Veldhuizen, Sisaman (Edinho), Yepe (Guiano)

Survey Results: 1256.1m +/-0.2m (orthometric height, EGM2008, 95% confidence interval)

Aug 28 – depart Seattle
Aug 29 – arrive Paramaribo
Aug 30 – buffer day
Aug 31 – Fly to Kayser, boat up Zuid River
Sept 1 – portage, boat up Lucie river
Sept 2 – boat to start of bushwhack, basecamp
Sept 3 – bushwhack to C1 in flats
Sept 4 – bushwhack to C2 in flats 
Sept 5 – bushwhack to C3 on ridge
Sept 6 – bushwhack to high camp
Sept 7 – summit, return to high camp
Sept 8 – bushwhack out to flats
Sept 9 – bushwhack out in flats
Sept 10 – bushwhack to Lucie, boat to West River
Sept 11 – boat to Baboonjari camp
Sept 12 – boat to Kayser
Sept 13 – fly to Paramaribo 
Sept 14 – depart Paramaribo
Sept 15 – arrive Seattle 

Suriname is one of the most forested countries on earth, with over 90% of the country covered in jungle. The country is a former Dutch colony located near the equator in South America, bordering Brazil, Guyana, and French Guyana. The highest point in the country, Julianatop, is deep in the jungle 100km from the nearest road. It is one of the least-climbed country highpoints on earth, with only five documented ascents before this trip. (Country highpoints with fewer ascents include Bhutan, Myanmar, Uzbekistan, Libya, and Australia). 

Climbing History

The region around Julianatop was explored by a Dutch team in 1926, but it is unclear if they climbed to the summit. In the late 1950s, the Dutch government began Operation Grasshopper, to build landing strips for planes throughout the territory for mapping and exploration. In 1959, Kayser airstrip, the closest to Julianatop, was completed. This is 65km from Julianatop. 

To access the area workers boated up the Lucie and Zuid rivers, then sawed and cleared out a landing strip in the jungle. Planes then flew in supplies and a half dozen buildings were constructed.

Also in the late 1950s, the Centraal Bureau Luchtkartering (CBL) conducted aerial photography of southern Suriname and used photogrammetry methods to create the first topographic maps of the area. The highest peak  in Suriname was identified to be Julianatop, within the Wilhelmina mountain range. The peak was named after the daughter of Queen Wilhelmina of the Netherlands. Many sources in Suriname cite an elevation of 1280m for Julianatop, and it is possible that number came from this CBL survey. (Source: East View Geospatial historical country mapping information). 

In June 1963 a 21-person Dutch team composed of members of the Dutch army, Dutch Geologic Mining Service, and staff from the New York Botanical Garden set out to climb Julianatop. They reported getting to a point 30m below the summit before turning around at the base of a tricky rock climb. (Source – De West newspaper article from Paramaribo, 1963). It’s unclear exactly which mountain they climbed. Julianatop does have a cliff on the south side, so it’s possible they got to the base of this cliff. But as per their report, they did not reach the summit. 

Between 1968-1978 updated triangulation measurements and photogrammetry was conducted in southern Suriname.  Topographic maps at scales 1:50k and 1:100k were created and released in 1981, though they were not consistent with labeling Julianatop. There is one peak 5km south of the highest point, with surveyed elevation 1080m. The highest point on the map, though, is 1230m+. The 1:100k map correctly labeled the 1230m peak Julianatop, but on the 1:50k map the 1080m peak was labeled Julianatop. This led to some confusion.

In 1975 Suriname became an independent country, and Julianatop became a country highpoint. 

In 2000, NASA flew the SRTM mission which took satellite-based elevation measurements around the world, including in Suriname. These measured Julianatop approximately 1230m, and confirmed it was the highest peak in the country, as the CBL 1950s and 1981 surveys had discovered. 

Early 2000s – Jime Healey made two unsuccessful attempts to climb Julianatop.

In 2006 a Dutch team led by Jim Healey, including Botty Sanches, Guido Robles, Kathleen Lieuw, Kie Song, Danielle Buitenweg, Peter Spiller, Menno, Winter, Daniel, and Chairu, climbed peak 1080, incorrectly thinking it was Julianatop. They summitted Sept 9. 

In 2007 another Dutch team summitted on March 13, but they also climbed peak 1080 instead of the true summit.  

In 2011, Martin Beems compared the two Dutch topographic map versions and discovered the labeling error. The correct Julianatop was the northern peak surveyed at 1230m. 

In September of that year Martin led an expedition accompanied by Jon Wunrow, Anthony Melov, Albert, Winter, and Edinho. They summitted the correct Julianatop on Sept 23, making this the first documented ascent. They first flew to the Kayser airstrip, which Martin’s family was responsible for maintaining. They took motorboats down the Zuid River and up the Lucie river to a point 18km away from the summit line-of-sight (location 3.52365, -56.50410) . They then bushwhacked up following the 2006 route to near peak 1080. They then continued on to Julianatop for a 31km route. The bushwhack took 5 days 6 hrs from the Lucie river. 

In approximately 2015 the Suriname government started a project to install radio towers around the country to improve communications for rural villages. They helicoptered an initial crew to the ridge just north of Julianatop, and the team chainsawed out a clearing for the tower. It’s unclear if the team climbed to the summit of Julianatop, but the clearing was 700m north of the summit along a ridge. The tower was never installed, but the clearing remained.

In February, 2022, Martin Beems led a second group in to the summit, following his previous route. Ginge Fullen (UK), Reid Larson (USA), Douglass, Ken, Winter, and Edinho/Sisaman joined. They summitted on Feb 22. The bushwhack took 3 days 6 hours from the Lucie river. 

In March, 2024, Steve O, Charlie Bicknell, and Alex Hubin made several attempts at summitting. They started from Kayser and kayaked down the Zuid River to near the Lucie confluence. They had trouble in rapids and got picked up by Winter in a motorboat back to Kayser. They returned to try again, and this time made it to the start of the bushwhack section and partway into the bushwhack. But they then had to retreat in heavy rain, paddled back to the Zuid, and were picked up by Winter again back to Kayser.  

In September, 2024, Ash Dykes, Matthew Wallace, Jacob Hudson, and Dick Lock helicoptered to as close as possible to the summit, landing at a spot just  5.5km away in an open area of the upper Coppename River (location 3.68475, -56.48764). This approach bypassed the river boating challenges and the main bushwhacking challenges. According to Guinness, they took 5 days 8 hours to reach the summit (though in a video of the ascent they say multiple times that they summitted on day 7). The team claimed a “fastest ascent of Julianatop” and got it recognized by Guinness. This is, of course, wildly inaccurate. The 2011 and 2022 ascents were faster despite starting significantly farther away and using a significantly more difficult approach. And the 2015 ascent could claim an ascent time of less than one hour by the helicopter-use standards of the 2024 ascent. In fact, the 2024 ascent is the slowest recorded. The team also claimed they discovered the source of the Coppename River, but this is also incorrect. It was discovered by the 2011 team that made the first ascent of Julianatop.   

In August, 2025, Charlie Bicknell returned with his father. They paddled from Kayser to near the confluence of the Zuid and Lucie Rivers. The Beems family then picked up Charlie’s father in a motorboat to return to Kayser. Charlie continued solo, and climbed Julianatop in five days from the Lucie River. He paddled back to Kayser by late August.  

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I’m working on climbing country highpoints and Julianatop first got on my radar in 2019. Jon Wunrow wrote a book about South America country highpoints, including a trip report from his 2011 trip. I bought his book, emailed with Jon a bit, and Jon gave me contact details for Martin Beems. 

I emailed a few times with Martin to coordinate a trip with fellow country highpointer Ginge Fullen. It didn’t end up working out for me, but Ginge went in 2022. He gave me all his beta for whenever I could make it work. 

I learned that timing is very important for a Julianatop climb. Suriname has a long wet season from April to August, then a long dry season Sept – Nov. There is a short wet season Dec-Jan, and a short dry season Feb-March. 

The optimal time to climb Julianatop is at the beginning of the long dry season in early September. This is best for multiple reasons. 

During the wet season the jungle floods and the bushwhacking can be very swampy and challenging. Bugs are much worse in this season, and daily rain gets everything wet. It is much easier when dry, and issues like swamp foot are not as problematic.

The river is very high during the wet season and rapids can be dangerous. But too deep into the dry season the river gets so low that progress by boat is challenging through shallow rapids. Ideally there is just enough water to get through the rapids, but not enough to make them dangerous. This sweet spot generally occurs in early September.  

In the spring of 2025 I had to cancel a previously-planned summer-long expedition, and this opened up September for me. 

Fernando and Viri were working on climbing country highpoints in the Americas and Fernando invited me to join for Julianatop. He was already in contact with Martin Beems about the trip. We set our dates as the first half of September, but Martin wasn’t available then. Martin’s cousin Scott Beems was available to lead the expedition, though, and Martin would provide all the beta. 

It’s possible to do a trip mostly independently, but this is riskier with lower chance of success and would rely on the Beems family for support and emergency rescue. We decided the safest plan with highest chance of success would be to climb in the style of the first and second ascent teams. 

We planned to follow the same route Martin pioneered, flying fixed wing in to Kayser, then boating and bushwhacking in. It seems like it would be poor mountaineering etiquette to helicopter in to so close to the summit like the Sept 2024 team did. This wouldn’t be very respectful of the difficulties overcome by the previous ascents, and wouldn’t feel as much like a proper old-school expedition. 

The optimum group size for safety and price for the standard approach and climb is four climbers and four guides. This fills up the plane going in, and allows two boats, each with motor operator and scout in front. Two boats are ideal for safety in case one motor fails or a boat capsizes. Serge was interested in joining and this rounded out the team. 

Scott was the leader, Dean assisted and was in charge of cooking and fishing, then Sisaman and Yepe were the lead motor operators and machete masters. Sisaman had previously climbed Julianatop with Martin in 2022 so would help with navigation. Yepe was indigenous Surinamese from a village in southern Suriname. He was an expert at traditional jungle survival and his skills would be very valuable. 

Surveying 

I was excited to bring my survey equipment up to the summit to measure a super-accurate elevation. There was no doubt based on satellite measurements that Julianatop was the highest point in the country. All other contenders were low enough to be outside the error bounds of the Julianatop elevation. But there was still uncertainty in the precise elevation of Julianatop. The 1950s survey using triangulation and photogrammetry could have at best measured the elevation of the top of the trees on the summit, and guessed the height of the trees to subtract off to get the summit elevation. So there could be a lot of error there. 

The satellite-based elevation measurement from 2000 was also subject to a lot of error. Dense trees can be misclassified as ground in satellite measurements, adding error. Also, satellite measurements were only taken approximately every 30m horizontal spacing, meaning spaces in between those measurements were approximated. Sharp summits like Julianatop would likely be underestimated. Even measured points have stated accuracy +/-16m. So the 1230m satellite measurement could be off by a lot, and likely an underestimate. Several other suvey data also exists. 

A 1971 1:1,000,000 US Operational Navigation Chart topographic map from the US Defense Mapping Agency has Julianatop surveyed at 1230m (source: https://maps.lib.utexas.edu/maps/onc/txu-pclmaps-oclc-8322829_l_28.jpg).

A 1993 1:500,000 Tactical Pilotage chart from the US Defense Mapping Agency Aerospace Center has Julianatop surveyed at 1237m (source: https://maps.lib.utexas.edu/maps/tpc/txu-pclmaps-oclc-22834566_l-28d.jpg).

Based on these exisiting measurements, it was unclear what the exact elevation of Julianatop was, except that it was likely between 1230m – 1280m. I think it’s important that the elevation of a country highpoint be known with high accuracy. Country highpoints of many European countries have been surveyed with dGNSS devices with sub-meter vertical accuracy, and the US country highpoint Denali has also been surveyed with this equipment. But most country highpoints in the world have not.

I have dGNSS survey equipment capable of measuring elevations with sub-meter vertical accuracy, and I’ve already surveyed 15 country highpoints with it. 

Julianatop would pose some unique challenges, though. Based on pictures from Jon and Ginge, the summit appeared to be covered in dense vegetation. This adds error if leaves block satellite signals. Also, the approach is long and it’s important to have as light a setup as possible to carry in.  

I have a Trimble DA2 now, which is the lightest dGNSS device available. My whole setup weighs only 1 kg. In order to acquire enough satellites I’d need to mount the receiver as high off the ground as possible. Hauling in a big tripod would be impractical, though. So I planned to make one on the spot lashing sticks together. Then I have a small flexible-leg tripod that can wrap around a small stick so I can attach the receiver to the stick tripod. I then use a tape measure to measure the tripod height and subtract that off at the end.  

For processing, I’ve previously discovered based on surveying state highpoints in MI and WI that there’s a special TrimbleRTX centerpoint site that automatically filters out cycle slips, which are errors caused by dense overhead tree cover. It requires at least one hour of data, though. As a backup, I can manually process using Trimble business center.  I hoped I could overcome the surveying challenges and get good summit data. 

The 2025 Expedition 

On Aug 28 I flew out of Seattle, and made it to Paramaribo on Aug 29 in the evening. I took a de Paarl taxi from the airport one hour to the city center, for about $40 USD. The airport is very far inland since Paramaribo is on the coast and the land is too unstable there to support a large runway.

That evening it rained in town, but I’d heard that the interior of Suriname is luckily drier this time of year than the coast. 

Serge and I stayed at the Eco Torarico hotel, and the next morning Aug 30 met up with Scott, Viri, and Fernando to go over logistics. All our flights had made it on time, so the planned buffer day wasn’t really needed. But I think it’s important to have a buffer day at the start of an expedition to avoid unnecessary delays right off the bat. 

Scott explained the difficulties we would encounter on the river and the jungle. The Amazon rainforest is different than my other jungle experiences in Brunei, Belize, and Caribbean islands. 

The rivers have many dangers, and it is a good idea to stay out of the water if possible. Electric eels can shock you with hundreds of volts, piranhas can bite a chunk out of your leg, and giant anjumara fish can get 20kg or more and bite a finger off with their big teeth. Unfortunately we would need to jump in the river occasionally to push the boats through rapids or shallow sections. 

In the jungle there are ticks on most plants, so it is pretty much inevitable to be covered in a dozen or more by the end of the day. It is a good idea to wear a hat with neck cover since they can drop from trees. You should also tuck in your long sleeve shirt, and tuck your pants into your socks or boots to minimize places bugs can crawl under your clothes. Luckily the ticks don’t carry diseases like in the US as far as I know. 

Various ant species can quickly crawl over you or drop from trees and bite. Bees are even scarier, and the best defense if you encounter them is to run or jump in the water. 

Mosquitoes are not as common in the dry season, and luckily Suriname has officially been declared Malaria-free as of 2025. But they can still carry Dengue and Chikungunya disease. 

Bot flies are like huge horse flies with a nasty bite. But more problematic is that they deposit eggs on mosquitoes. If you get bit by one of those mosquitoes it deposits the bot fly egg under your skin and the larva will eventually grow. You have to cut it out or cover the hole with Vaseline to suffocate it. Various flies can transmit leishmaniasis, which is a similarly undesirable instance of a larva growing under your skin. 

Jungle animals can also pose problems. Herds of pingos (wild pigs) roam the jungle, and they can be dangerous if they attack. The best defense is to climb a tree. Jaguars and big 8m-long anacondas are around, but they supposedly don’t attack people. Giant anteaters could attack in rare instances, but it’s unlikely.

I even heard rumors about uncontacted Indian tribes in the area that might be unfriendly, but I’m not sure how solid the evidence is about that. One night Yepe said he heard a call in the jungle that sounded human, though.  

The ideal clothing for the jungle is thick pants and a long sleeve shirt that the bugs can’t bite through and that are resistant to getting torn by thorns. Many plants have thorns in the jungle. If you stumble and trip, you should not reach out to grab the nearest tree for support. It’s best to just roll to the ground. 

Shoe choice is a bit more complicated. For the river a pair of water shoes like those for kayaking is good. This allows you to walk through the river pushing the boat without worrying about stepping on sharp rocks. For camp a pair of flip flops is nice. 

For jungle bushwhacking the locals generally wear rubber boots. These allow for wading through shallow water, and they are also harder for bugs to get past. But they have disadvantages. If water gets in, it stays in and keeps your feet wet. Sweat doesn’t get out, and blister issues are more common. And the rubber boots have pretty flexible soles, which makes getting up or down steep muddy slopes difficult. 

The other option is leather hiking boots (Scott’s uncle recommends the Finnish brand Nokia). These are good for muddy slopes and are less likely to cause blister problems. But to cross creeks you either have to take them off or just get them wet, and then they stay wet. Also, bugs can get to your ankles more easily. 

We hoped by following Scott’s advice about clothing we could mostly avoid bug problems. And we all decided to wear hiking boots we were comfortable with. 

Aug 31

We took a taxi in the morning to the domestic airport nearby, and met the whole team there. We left our passports and wallets with Scott’s uncle, then loaded up the small Cessna 208 caravan 12-seatter prop plane. 

We took off at 9am for a 90 minute flight. En route we did a slight diversion to go directly over Julianatop, but unfortunately it was stuck in the clouds. 

We landed at Kayser by 1030am, and the pilot moved the plane over to the far western tip of the landing strip closest to the river. 

The landing strip is all dirt and grass, and is mowed and leveled regularly. The area has six buildings built in the 1950s from Operation Grasshopper. Winter has been in charge of maintenance for many years, and often is the only person residing at Kayser. The compound is only occupied in the dry seasons, since the runway floods in the wet seasons and is unusuable.

The compound has a tractor, bulldozer, excavator, and other machinery. They were all flown in and are used for maintenance. 

We were very efficient unloading and brought our gear directly to the Zuid River along a short path. Martin was there and helped load. Charlie Bicknell’s father was also there, and we learned that Charlie had recently summitted Julianatop and was paddling back. His father had paddled with him for the first few days to the Kleine Temper rapids just before the Lucie River. He then left his kayak there and was picked up by motorboat and returned to Kayser. His father gave us a package to pass on to Charlie when we crossed paths with him. 

We loaded all four climbers in one boat, and most of the gear in the other. Scott and Yepe alternated manning one motor, and Sisaman manned the other with Dean as scout. The scout identifies submerged rocks to avoid, and helps steer the front of the boat with a paddle. Flat sections of river can deceptively have rocks and logs barely below the surface, indicated only by subtle ripples. General wisdom seems to be hugging a shoreline with dense brush on shore is where the water is often deepest.

I was impressed with the motor skills required for this trip. The motor operators have to be able to quickly tilt the motor forward if it clips a rock, and swing it left and right quickly to maintain control in tricky rapids. Sometimes they need to drive backwards towards rapids to scout them out, before turning around to go through the deepest channel. 

Nearly all gear was in waterproof barrels or waterproof bags. There’s a real risk of a boat flipping in a rapid on the river and we wanted to be prepared. The 2022 expedition flipped one boat, and it took a few years for the Beems family to recover it. They had to wait until late dry season when the submerged boat was visible. They then kayaked in and tied it to a tree. They then waited till the wet season, pulled it out, and floated it back. Since then all boats have been modified with extra flotation so they will float even if completely full of water.

We were loaded up by late morning and soon headed out. The first few hours of river were relatively easy, and the river was deep enough that we didn’t hit any shallow rocks and didn’t need to negotiate any rapids. 

By mid afternoon we reached tukunari stone camp (peacock bass stone camp), and pulled over. There’s a small wooden shelter here with a metal roof and places to tie up hammocks. Sisaman discovered a big tarantula in camp and started letting it crawl over him. Apparently tarantulas don’t bite unless seriously provoked, so aren’t too dangerous. I handled it a little bit too. 

We relaxed by the river while Sisaman and Yepe caught a few piranhas to eat. We then went to bed shortly after sunset. 

Sept 1

Charlie had paddled up to camp the previous evening and we met him in the morning to give him the package from his dad. He had successfully summitted Julianatop a week or so earlier, making the fifth known ascent.

There were a few rapids in the morning that were too shallow to motor through. So the strategy was the motor was tilted out of the water and we all got out of the boat. Then four people held onto the boat and carefully dragged it through the rapids. The boats were shaped so they can still float and be pushed through very shallow water, only a foot deep, if not too heavily loaded.

Interestingly, on the shore of the upper rapids I noticed some deep parallel gashes in the rock. These were from old indigenous Indian groups sharpening blades on the rocks. 

We took a short break at Baboonjari camp lower down river. This camp is very luxurious, with a cook shelter and two separate sleeping shelters. Below this we had to push the boat through one more rapid before reaching the Kleine Temper rapids by early afternoon. 

This is a major stretch of rapids that a motorboat cannot be pushed through. It must be portaged around. The early Dutch expeditions in the 1950s cut a 500m trail through the jungle around the portage, and the trail is still used today. 

We first shuttled all the climbing gear, motors, and fuel tanks down the trail. We then found big round roller sticks to lay perpendicular in the trail. This would make it easier to push the boats. We then pushed and pulled each boat along the trail, with a rope in front and people pushing in the back.

This actually went faster than I expected, with the light aluminum boats and eight people working. Within a few hours we had all the gear around the rapid and continued down river. 

It was now only 2km from the Lucie River confluence, but the river got more complicated. For one rapid we all got out and Sisaman and Yepe took turns motoring the boats carefully through. Farther down river the channels got complicated and it took a while to find the deepest line, which we still had to push the boat through. At one point when Sisaman was scouting a line Dean cast a line in and caught two giant anjumara that we would eat for dinner.  

We finally reached the Lucie, then started motoring up river. One rapid took a few tries, and we eventually got out and pushed. By sunset we took out at a nice little side stream and set up camp. We ate an excellent dinner of fresh anjumara.

This day illustrated the importance of having separate clothes to sleep in. We would get soaked from  being in the river pushing the boats, so it was nice to change into a dry outfit for bed. We all had hammocks, which made it easier to find a campsite since the ground didn’t need to be flat. 

Sept 2

We continued boating up the Lucie River, which had a handful of rapid sections that required getting out and pushing. Unfortunately one of the motors has issues with the spark plug wires, but Scott is an expert mechanic and got it back working. 

As we got deeper into the jungle we saw more wildlife. Red and blue parrots were common, always flying in pairs. We saw one Capybara on shore, and a handful of iguanas.

The river got very narrow farther up stream, and we pulled out just before it takes a sharp 90 degree turn to the southeast. This was at a strategic location at nearly the closest point to Julianatop, but just before that point. The bend occurs just after a stream that is low elevation and very swampy with dense bushwhacking. By taking out before this we could follow slightly higher elevation hilly terrain that would likely be more open and less swampy, meaning easier bushwhacking. Decisions like these are critical when bushwhacking, and can result in twice as much progress per day. 

As we pulled out Scott saw a curassow bird in a tree and shot it for dinner. We unloaded the boats and brought the gear up a steep muddy bank full of tapir tracks, then onto a nice flat shoulder. Shortly afterwards Scott noticed a pingo (a small pig) nearby, and that also made it onto the dinner plates. 

We dragged the boats high on the bank, tied them up, and removed the motors so they’d be ready to stay there for a week while we bushwhacked.

I had a bad ant experience while setting up my hammock. I didn’t inspect a tree closely enough, and had to hug it to get the rope around. Many ants quickly crawled onto me and started biting. I threw off my shirt and brushed them all off, but then they kept magically appearing. It turned out they were dropping down on me from branches above! I picked a new set of trees farther away and had a better ant-free experience. 

Sept 3

The next morning was our first day bushwhacking. We suited up in bushwhacking gear of pants tucked into shoes, long sleeve thick shirts that wouldn’t rip, and hats with neck covers.

We had to try a few different navigation and gear distribution strategies before finding the best solution. We first started with group gear equally distributed, with Sisaman and Yepe cutting trail in front, then Serge next with a compass telling them whether to go left or right, then me next with my gps on my phone telling Serge which heading to follow. I was using the OsmAnd app, which Scott showed me has the best topographic maps for Suriname. At the end of the pack Scott and Dean were placing flagging on trees to help mark the route, and also making cuts on trees with the machete to mark the route. This would help us make a speedy return trip.

In general we tried to maintain a constant heading roughly paralleling a small creek at a constant distance, and aiming for the base of a prominent ridge to the east of peak 1080. We hit a few dense swampy areas we had to skirt around but the route was generally good. 

We had to take frequent breaks, though, because the load distribution was not ideal. Sisaman and Yepe were expending too much effort macheteing while carrying heavy loads. By mid afternoon we decided on an early stop at a small stream. We’d covered 3.5km in about 5.5 hours. We set up hammocks and had leftover pingo for dinner with rice.

Sept 4

This day we tried an improved bushwhacking strategy. We left as much extra gear as possible in a cache and planned to rely more on food from the jungle. Sisaman would go in front with no pack, but with the compass. We would tell him a heading and he would follow that. 

Yepe would go next with just a light pack and machete also. I would take extra weight since I wasn’t doing any macheteing or navigating and I was used to carrying big packs. 

This strategy was much more efficient all around. In general we would average about 1 km per hour, and take a break every km or every creek. There were enough creeks that I could get by just carrying one liter of water at a time. We put in a full 8 hours and covered a bit over 6km line of sight.

It might sound like a slow pace covering just 1km per hour, but that is pretty good in dense jungle carrying heavy loads. In a previous trip with Serge bushwhacking in the jungle to get the Brunei highpoint we only covered about 200m per hour for nine hours. So 1km per hour was great. 

We found another small stream and set up a good camp. In general along the flat approach before the base of the mountain we found usable water sources every km or so, which made it very flexible to choose where to camp. 

Sept 5

The next day we followed the same strategy and made good progress, reaching the last major creeks by mid day. We waded across two, then found good log crossings on the next two. There was an electric eel in one creek that luckily had a log crossing.

The last creek crossing marked the end of the long flat section and left us at the base of the mountain. Here we took a long break and caught a few anjumara. We packed them up for dinner. Yepe made a traditional backpack for the fish using palm fronds and bark strips and carried it up. 

From the last creek we followed a ridge north through mostly open terrain, crossed over peak 505, then dropped down to the next saddle. There we found a small creek and set up camp. We’d covered 5.5km in 8.5 hrs. 

Sept 6

We continued following the ridge north then west until approximately 840m. This ridge extended up to peak 1080, the peak incorrectly labeled Julianatop on one of the 1981 topo maps. 

Following Martin’s beta, we then traversed at that elevation across the steep north face. This had several areas of denser vegetation and a few steep muddy sections near a waterfall.

 

By late afternoon we finished the traverse and dropped down the north ridge. There we got our first view of Julianatop across the valley from a break in the canopy. It had distinctive long rock slides on the steep south face and was a relatively sharp summit. This was good news for surveying since it looked straightforward to locate the highest point to mount the receiver.

We dropped to the saddle just north of peak 1080, then found a small creek 100m to the west where we set up camp. This would be our highest camp on the mountain. The temperature was noticeably a bit cooler at night, making for more comfortable sleeping (for me). 

That evening I tried to take some test measurements with the dGNSS receiver, but it could only acquire 5 satellites. This wasn’t enough to get an elevation. The problem was the dense canopy overhead blocking signals. I hoped the summit would have better conditions. 

Sept 7

This was our summit day and we packed light with just food, water, and survey gear. It would be about 4.5km to the top. We left at 8am and followed Martin’s route, making a rising traverse across the south face to hit the east ridge around 950m. This avoided some challenging rocky sections on the ridge proper. 

On the ridge crest we passed evidence of a pingo herd foraging in the brush. Then shortly after crawling up a rocky chasm, Dean saw a jaguar perched on a boulder. It soon jumped into a nearby cave guarded by dozens of roots hanging down. 

We all congregated at the entrance trying to get a glimpse of the jaguar, but the cave appeared to be deep and we didn’t see it. Nobody was brave enough to venture inside, so we continued on. It seemed like the perfect place for a jaguar lair, very deep in the jungle with a huge supply of pingo nearby. 

We followed the east ridge up to the north ridge, cresting it 700m north of the summit. There we saw a handful of felled trees that had been chainsawed down. The forest had started growing back around them and they looked old. This was evidence from the 2015 helicopter ascent where the team was lowered down and sawed out trees for a planned radio tower. We didn’t see any tower, though.

From there we continued south, and pushed through the final section of dense tall jungle grass to reach the summit by 1:45pm. 

The grass on the summit was all matted down from Charlie’s ascent, and it was luckily a sharp enough peak to easily identify the highest point. There was a rotten old Suriname flag sticking out of the ground there, possibly from the 2022 ascent. 

I took out the DA2 dGNSS receiver and tried testing out how many satellites it could pick up. Like before I only got 5, even holding it above my head. I was getting worried I wouldn’t get any usable data. The overhead canopy was more open here, though, and I suspected if I could get it even higher that would make more sky available. 

Scott found a long 2.7m stick and two smaller ones and fashioned a tripod with some string. I put the DA2 on my small flexible leg tripod, wrapped the legs around the tip of the stick, then plugged in the battery and taped it to the stick. We then erected the tripod and I soon picked up 30 satellites! That was perfect. The extra height had made all the difference. I used a tape measure to measure the height of the receiver above the ground, and I would later subtract that off my raw measurements.

We hung out on the summit for an hour taking pictures. There was a good view to the south above the rock slides. By 3pm we headed back down. It was much faster following the route we’d already macheted clear, and we were pushing hard to beat darkness.

By just before 7pm we reached camp, as a small thunderstorm dropped a bit of rain. It didn’t last long, and was some of the only rain we had the whole trip. 

Just after dark a herd of dozens of pingo wandered very close to camp. They made loud barking sounds like dogs and didn’t appear at all afraid of us. I don’t think they’d encountered people before. We had fresh meat to eat that night and the next morning. 

Sept 8

The hike out went much more quickly since we already had a great trail cut out, and had lighter packs from eating down the food. 

We followed our ascent route back around peak 1080, then all the way down to the big creek at the start of the flats. There we set up camp and caught fresh anjumara for dinner. I went for a quick swim that felt good. 

Sept 9

We caught another anjumara for breakfast, and made fast progress through the flats along our trail. That evening we reached all the way to our original first jungle camp, just 3.5km from the Lucie river. 

Sept 10

We packed up our cached gear, then hiked back to the Lucie River in a few hours. The boats were still in good condition, and we loaded up and started down by noon. 

Unfortunately, in one rapids section Sisaman’s boat flipped and got pinned sideways against a rock. He and Dean were fine, but all the gear started floating down the river!

The climbers boat raced down and retrieved it all. We then motored back to the flipped boat. We waded over, pushed it out from the rock and flipped it over. It was great to have 8 people pushing together since it was pinned in pretty tight. Luckily it still floated, and we bailed out the water. 

The motor still worked fine, so we continued down river. The water was noticeably lower after the past eight days of no rain, and a few rapid sections were different. We just had to get out to push once, though, before reaching camp at the confluence with the West river. 

We caught a piranha and a huge anjumara for dinner. For reference, the piranha has many small bones in the meat, and the anjumara has fewer, so the anjumara is much better for eating. 

Sept 11

In the morning Dean caught a caimen and cleaned it to eat later. We soon hit the Zuid river and started boating up. 

The rapids were tricky going up, and we had to find different lines than when we descended. One rapid was narrow and rocky, and I had to get out in an awkward position and push really hard on the boat. I pushed hard enough that my shoulder actually dislocated, and I quickly jumped on shore in pain. Luckily I know a technique to get it back in quickly. I clasped my hands together, put my knee in between, relaxed as much as possible, then pushed my knee hard into my hands, stretching out my arms. My arm popped back in place, and the pain subsided. But it was still sore.

I laid on the ground while the rest of the group finished the pushing job. Then I jumped back in the boat to continue. I decided to take it easy the rest of the day and not risk further injury. So I was just a photographer for future rapids. 

The jungle portage section took a few hours of ferrying gear and pushing the boats, and we finished by early afternoon. We continued up river, but progress was slow since the water was so low and so many rocks were exposed. 

By sunset we were still 1km away from our planned camp at Baboonjari. Then it started raining. We continued on cautiously, getting thwarted by one rapid and having to get out and push. The bugs swarmed towards any illuminated headlamps, which made navigation more challenging. But we eventually reached the camp and enjoyed the luxury of the shelters.

Sept 12

The next morning we boated for another 4.5hrs, pushing the boats a few times, before making it to Kayser. There we relaxed and took showers, before flying out the next morning to Paramaribo. 

Survey Results

I processed the results using TrimbleRTX accessed via centerpoint, which removes cycle slip errors caused by dense overhead tree cover. This gave me an ellipsoidal elevation, which I converted to orthometric using EGM2008 geoid (the most accurate for Suriname). I did this using the NSF/USGS Unavco converter (https://www.unavco.org/software/geodetic-utilities/geoid-height-calculator/geoid-height-calculator.html)

This gave an elevation of 1256.1m +/-0.2m. This is now the most accurate elevation of Julianatop to date.

The satellite measurements that gave 1230m were under by 26m, which isn’t too surprising to me. Julianatop is a relatively sharp summit with a cliff on one side, so it’s likely the satellite measurement missed the summit and hit a lower part of the mountain. It’s common for satellite measurements to undermeasure sharp summits. 

The 1950s Dutch survey that measured 1280m was 24m too high. I expected this to likely be an overestimate since the surveyors could only see the tops of the trees on the summit with a theodolite or aerial photography, not the ground. It’s interesting that the true height is almost midway in between the other two height measurements.

 

 

 

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