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800 Kanawauke Rd, Stony Point, NY 10980
The pin marks the address the race lists, which is usually the start. The organizers have not shared a course map with us yet.
Aggregated from official results for Diamond Mountain Triathlon (USAT Sanctioned). Individual finisher names are not stored here.
At the 2026 Elite/Advanced Triathlon (0.5mi/15mi/2mi) First Waves, the fastest tenth finished in 1:25:13 or better, the top quarter in 1:32:47, and half the field in 1:45:53; the last tenth came in after 2:17:35.
At the 2026 Adult Duathlon (2mi/15mi/2mi), the fastest tenth finished in 1:23:45 or better, the top quarter in 1:30:02, and half the field in 1:51:53; the last tenth came in after 2:10:23.
| Age | Women | Men |
|---|---|---|
| 20-29 | n/a | 1:30:59 |
| 30-39 | n/a | 1:26:44 |
Groups with fewer than five finishers are left out. Awards vary by race; check the race's rules.
Where a finish time would have placed in 2026.
Up 16 percent since 2025.
All events combined, from official results.
From 2025 to 2026, the field went from 36 to 47 finishers, and the median time dropped from 1:48:45 to 1:45:53.
| Year | Finishers | Median | Fastest tenth | Winner |
|---|---|---|---|---|
| 2026 | 47 (+31%) | 1:45:53 | under 1:25:13 | 1:14:17 |
| 2025 | 36 | 1:48:45 | under 1:25:10 | 1:13:24 |
From each year's official results for the Sprint Triathlon; virtual options are left out.
What the organizers of Diamond Mountain Triathlon (USAT Sanctioned) cover on their registration page, in brief.
Course
Triathlon: 0.5mi swim, bike is one 15mi lap, 2mi run. Duathlon: First and 2nd run are the same 2 miles, bike is one 15mi lap: Swim start: Swim out arch: Swim out guide signs: Tray to rinse feet from sand at run-in gate: Bike course (1 lap…
Organize this race? Add details or a correction
Welcome to Diamond Mountain Triathlon,
hosted in the scenic heart of Harriman State Park. The course features a calm lake swim, a rolling 15-mile bike loop with spectacular views, and a fun lakeside run to the finish. The event is beginner-friendly while still rewarding strong competitors.
Rain or shine, we race — and we’re excited to share the course with you.
What the event offers:
Relaxed and convenient midday start
Police-controlled intersections
Course signage and volunteer support
Race photographers
Free public parking
Junior athletes race Duathlon with adults for free
Junior athletes race Triathlon for free and may have a separate start
Finisher medals for all participants
Awards for Top-3 Men & Women in both Triathlon and Duathlon