Trail ultramarathon · USA
26–27 June 2027 · Olympic Valley → Auburn, California
100M: Sat, 26 June 2027
The world's oldest 100-mile trail race. From the snowy Sierra Nevada to the scorching American River canyons. 100 miles, 5,500 m of climbing, and up to 43°C in the canyons.
2027 dates confirmed
Event and distance dates were checked against the organizer schedule.
The mapped GPX is carried forward from 2026 until the new course is verified. Use it for course research, then re-check before race day.
Date sourceEntry · 100M · 2027 edition
Places in 2027 go by lottery. Applications close Sat 21 Nov 2026. Results: Sat 5 Dec 2026.
Requirement: a qualifying race finished within its time limit between 3 November 2025 and 8 November 2026.
Subscribe to these entry dates (updates when the organizer's dates change and we recheck them) · Download .ics. Separate from any training calendar; remove it any time in your calendar app.
From the organizer's page, checked 1 Oct 2026. TrailSplits does not know whether you have a place; the organizer is the final word.
Western States 100 is a trail ultramarathon scheduled for 26–27 June 2027 in Olympic Valley → Auburn, California, USA. TrailSplits currently includes one mapped course for this event, with course maps, elevation profiles, weather context, and pacing tools for the uploaded GPX data.
How to get a place: A qualifying race finished within the qualifying period, then a lottery. For the 2027 race, lottery registration is open for three weeks in November 2026 and the lottery is drawn on 5 December 2026. Organizer's page, checked Thursday 1 October 2026.
TrailSplits is a free, independent route & pacing companion — not the official race. Visit the official Western States 100 site →
Racing more than once next year? Add 100M to a season and see whether your races work together.
Inspect the official course track on a topographic map, through its elevation profile, or in 3D.
› running direction two lines: out and back on the same path kilometres
Selected distance
Vert-focused blueprint with route-finder links into the Planner.
Prepare and return
Keep this course, its training plan, calendar and future course updates together in your private My Races page. Saving does not publish your workouts, pace or progress.
Western States 100 100M — 2025 edition. 300 finishers.
Estimated finish-time percentiles, modeled from the 2025 winning (14h 30m) and median (25h 30m) times — a guide, not official splits.
Race route lab
Open the official course in Planner, then choose a nearby start point to build a shorter loop that matches the course demand. This course averages about 32.4 m climb per km.
Sat, 26 June 2027
Send to your watch
Get the official course as a clean GPX or a Garmin TCX course, with step-by-step instructions to load it onto a Garmin, COROS, Suunto, Wahoo, or Komoot — free, no account needed.
Compare your training
See how faithfully your rehearsal route matches the real race. The official course for 100M loads as Route A — upload your training route to compare distance, elevation gain, estimated time, and how much of the course you actually cover.
Course analysis
See the 100M course broken into its major climbs and descents in order — length, gain, average grade, and steepness — so you know where the crux is and how to pace and fuel it.
Race-week reminders
A free browser notification in the final week — the course crux, the weather window, and loading the GPX onto your watch. No app, no email, no account.
Western States 100 2027 is scheduled for 26–27 June 2027 in Olympic Valley → Auburn, California. Check the official race site for registration deadlines and final details.
161.1 km with 5,220 m climb. The longest course is 161.1 km with about 5,220 m of vertical gain — a demanding mountain course.
The 100M course has a 30-hour cut-off, an average of 11.2 min/km to finish in time. TrailSplits' cut-off pacer shows the buffer at each aid station.
Yes. TrailSplits gives you the course map, an interactive elevation profile, a 3D flyover and a downloadable GPX for every mapped distance — free and with no sign-up.
Each distance has a free, course-specific 16-week training plan built around its distance, vertical gain and cut-offs, plus a pace and cut-off calculator.
No. TrailSplits is a free, independent route and pacing companion. For registration and official rules, visit https://www.wser.org.
Load the GPX directly into TrailSplits for surface analysis and terrain intel.
Install TrailSplits — a free app you add straight from your browser — and download the 100M course to your phone. Explore the route and elevation offline before race day, then follow it with no signal on the day. No app store, no account, no subscription.