Skip to content
Endurance AnalyticsEndurance Analytics
  • Calendar
  • Trail Finder
  • Geo Quiz
  • Blog
  • Trail Buddy
Trail runningBiathlonSkiingSkimoOlympicsCalendarTrail FinderGPX AnalyzerRace Pace CalculatorChallengesTrail BuddyComparePricingConnect AIBlog

Know the course before you run it

© 2026 Endurance Analytics. All rights reserved.

Privacy policyTerms of serviceRefundsContact
  1. Home
  3. Trail running
  5. 2026
  7. Lake Sonoma
Lake Sonoma
100km10050km5021km21

Lake Sonoma LS 100k

100.0km·4570m+
April 11
Geyserville,
United States
itra
The plan will appear closer to the race. For now, check a previous season's plan.

Race Pace Calculator · GPX Analyzer · Trail Finder

Other races: United States

  • Dead Horse Ultra · Dead Horse 50 MileNovember 14, 2026 · 80.5km · 1492m+
  • HOKA Pacific Trails California by UTMB · Pacific Trails 50KNovember 13, 2026 · 50.0km
  • Dead Horse Ultra · Dead Horse 50KNovember 14, 2026 · 50.0km · 855m+
  • Dead Horse Ultra · Dead Horse 30KNovember 14, 2026 · 30.0km · 527m+
  • Dead Horse Ultra · Dead Horse 15KNovember 14, 2026 · 15.0km · 284m+

Read

  • Types of Runs and What Each Workout Actually Trains
  • Hill Training for Trail Runners: Train the Descents
  • Downhill Running Muscle Damage: Why Descents Wreck Quads

Full calendar: United States100K trail race calendar

About Lake Sonoma LS 100k

Lake Sonoma LS 100k is the 100km ultra trail at Lake Sonoma 2026 (Geyserville, United States). The race starts on April 11, 2026.

Course

The course climbs 4570m+. With 46m/km of climbing, this is a true mountain course with sustained climbs and descents.

Results

140 finishers completed the 2026 edition. Men's winner: Ryan Sullivan (United States) in 8:36:09. Women's winner: Fiona Pascall (Great Britain) in 10:13:24.

This page has the full results and splits, a pacing and nutrition planner, a gradient matrix, an interactive elevation profile and historical weather for Lake Sonoma LS 100k.

Other distances of Lake Sonoma 2026Lake Sonoma LS 50k (50.0km)·Lake Sonoma TS 13.1 Mile (21.0km)