Jamaica Highpoint Survey

 

Blue Mtn Peak and Middle Peak, Highpoints of Jamaica

June 23, 2026

Eric Gilbertson 

16 miles, 4700ft gain

Results (EGM2008, 95% confidence interval errors)

Middle Peak: 2254.02m +/-0.04m

Blue Mountain Peak: 2253.99m +/-0.03m

SE Peak: 2253.16m +/-0.14m

Blue Mountain Peak and Middle Peak are tied for the country highpoint.

I’d previously climbed Blue Mountain Peak in Jamaica in 2013, but in March of this year I learned there may be another candidate for the country highpoint. In late March Rob Woodall surveyed three contenders in the summit area with a Trimble DA2 and found them tied for the same elevation within the measurement errors. The peaks were Blue Mountain Peak, Middle Peak (90m away) and an unnamed peak to the SE (120m away). 

Rob took 20 minute measurements with errors around +/-0.3m. I want to be as rigorous as possible in my country highpoints project, and I definitely had not climbed the SE candidate on my last trip. So I decided to return and try to take even more accurate measurements to try to resolve any uncertainty. 

I have two Trimble DA2 GNSS receivers, and I planned to take 4 hour measurements on each summit. That’s usually about the cutoff when errors reach about as low as possible. I would bring a 2m antenna rod and tripod to help reduce errors in the dense foliage. 

My regular tripods are big enough that they count as oversized luggage, but I didn’t want to pay that extra fee for an international trip. So I found a small tripod on Amazon that would accept a regular surveying antenna rod and bought that. It would be a little less stable than my big tripod, but I figured I’d be surveying in the trees so shouldn’t have to worry about wind.

I landed in Kingston, Jamaica in late afternoon June 22 and rented a Toyota RAV4 from Avis. The road up to the starting point at Pennlyn Castle is rough enough to require 4wd and high clearance. 

I had a bunch of other expensive climbing equipment in my luggage for the next trip and I didn’t want to risk that getting stolen from the car if I camped out and left the car at the trailhead. So I paid to stay at Jay’s Guesthouse, which is about as far up as you can reasonably drive on the route. That way I could store my gear there while I hiked and I knew it would be safe.

I made it up to Jay’s Monday evening, and the road indeed benefits from 4wd and high clearance. I spent the night at Jay’s, then started up at 315am the next morning. I had a lot of surveying time ahead of me and didn’t want to get stuck surveying during afternoon thunderstorms 

I hiked up the road, up the trail through familiar areas like Portland gap, then topped out around 6am. There were two other hikers and a guide up there. I think they started at 2am.

The first of the three summit candidates reached is on the left just before the shelter on a grassy overgrown trail. There’s a bench on the flat top and this is Blue Mountain Peak. The next summit is beyond the shelters and has the big metal trig station on top. The highest ground is about 20m south of the trig station. This is Middle Peak. The last summit candidate is reached by following the trail to the lookout farther east on the edge of a cliff, then bushwhacking SE to the next local maximum, about 120m away from Middle Summit.

According to a sign on Middle Peak, Blue Mountain Peak and Middle Peak were surveyed by the British to be the same elevation, 2256m. The trig marker was put on Middle Peak because it had a better view to other survey trig markers. 

I first bushwhacked to the SE summit and mounted the DA2 on the 2m antenna rod on the tripod at 630am. Then I hiked back to the middle summit and mounted the second DA2 on a smaller tripod at 645am.

I hung out for four hours taking pictures and taking a nap. Then I took down the equipment and moved over to Blue Mountain Peak. At first I mounted the 2m tripod, but it got blown over by the wind. Luckily the DA2 is built to survive falls like this. So instead I set up the small tripod and started logging data at 11am. 

I walked all over the summit area taking pictures and took another nap in the new shelter. Interestingly, the old shelter, built in the 1960s, had been demolished. Matthew and I had spent the night there in 2013 and it was already in tough shape then. The new shelter is just a bench and a roof with one back wall and is not intended for camping out. Indeed, the entire upper mountain became a UNESCO site in 2019 and after that camping appears to w prohibited on the summit (or at least discouraged).

By 3pm I logged another 4 hours of data, then packed up and hiked down. I made it back to Jay’s by 530pm and had a nice dinner. 

I processed the data with TrimbleRTX accessed via surveytools. This site filters out cycle slip errors from overhead tree cover. I found:

Results (EGM2008, 95% confidence interval errors)

Middle Peak: 2254.02m +/-0.04m

Blue Mountain Peak: 2253.99m +/-0.03m

SE Peak: 2253.16m +/-0.14m

Interestingly, this means Blue Mountain Peak and Middle Peak are tied for the same elevation. The error bounds overlap quite a bit, so it is not possible to conclude from this data whether one is taller. This is consistent with the British survey, which also found them tied in elevation. 

In this case, when the top-of-the-line GNSS equipment with four-hour measurements has the two summits tied in elevation, and traditional survey methods also have them tied, I would conclude they are tied. Thus, climbers need to climb both summits to claim credit for the country highpoint. 

The SE summit is low enough to definitely not be the highpoint. The errors for the SE summit were higher because it was in dense jungle cover, while the other two peaks had open sky views. But the errors are still small enough to conclude the SE summit is definitely shorter than Blue Mountain Peak and Middle Peak. 

 

 

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