Nicknamed the Race Across The Sky, it is run entirely at very high altitude.
A plan built from your answers and your race date.
The Leadville Trail 100 Run takes place around Leadville in the Colorado Rockies. The route uses forest roads, mountain singletrack and long runnable sections, with an out-and-back pass crossing that shapes the whole race. Every kilometre is run at very high altitude, in an exposed and largely treeless landscape.
9 km, known as the Race Across The Sky. The out-and-back format lets crews work the same access points twice, outbound and on the return.
One format only.
| Format | Distance |
|---|---|
| 100 miles | 100 mi |
Organizer information, checked on September 21, 2026 · leadvilleraceseries.com
A build for this distance usually runs 12 to 24 weeks. Counted back from race day, that puts the start somewhere between March 1, 2027 and May 24, 2027.
These ranges are working conventions, not a research finding — no trial has compared plan lengths against each other. What matters more is that the plan was built for the weeks you actually have, rather than shrunk down from a longer one.
When to start
March 1, 2027
→ May 24, 2027
This list keeps growing; it draws no line. A race that is missing is prepared for in exactly the same way.
Secure payment with Stripe. Then allow about 30 minutes for your profile, in several sittings if you like.
