The Spirit World 100 is 102 miles on gravel and ranch roads through the San Rafael Valley borderlands, with about 6,400 feet of climbing that comes as rolling grades repeating all day rather than one named climb. Early November brings a cold pre-dawn start and warm, dry afternoons, and there’s a hard six-and-a-half-hour cutoff near mile 68 that ends the race for anyone behind it.

This is a twelve-week plan for the Spirit World’s distance and rolling climbing, built around four to six hours a week. Most rides build endurance or steady climbing, because that’s what a long day of repeated grades asks for and the limited hours go furthest spent on it.

WHAT'S INSIDE

• Structured workouts on your calendar, with real power and heart-rate graphs


• Strength work built in, with video walkthroughs


• Weekly notes from me, plus the Gravel Grit mental program


• A testing week and a mid-plan retest, so the plan runs on your real numbers


• The full Spirit World 100 guide — terrain, gearing, fueling