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Fall trail races near Seattle (2026)

7 trail races on the calendar from September to November, starting with Lake Washington Half Marathon on Saturday October 17. 1 of them publish an upcoming price increase, so signing up early saves money.

All fall races5K races (45)10K races (22)Half marathons (15)Marathons (2)Trail races (7)

• Sat17Oct

  Lake Washington Half Marathon

  Sat Oct 17 · 8:00 AM · Kirkland · Eastside & South King

  Half marathonTrail
• Sat24Oct

  West Seattle Monster Dash

  Sat Oct 24 · 9:30 AM · Seattle · Seattle (city)

  5KTrail

  from $40Goes up Oct 19
• Wed28Oct

  Ten Trails Active Club Trot n' Treat Relay Scramble

  Wed Oct 28 · 6:30 PM · Black Diamond · Eastside & South King

  11KTrail
• Sat31Oct

  Cougar Mountain Trail Run Series (October)

  Sat Oct 31 · 8:00 AM · Bellevue · Eastside & South King

  5K7.6 miles19.5 miles50KTrail

  from $40
• Sun8Nov

  Run the Bay

  Sun Nov 8 · 8:00 AM · University Place · Tacoma & South Sound

  5K10KHalf marathonTrail

  from $52Goes up Nov 8
• Sat21Nov

  Jumping Mouse Turkey Trot

  Sat Nov 21 · 9:00 AM · Port Townsend · Tacoma & South Sound

  1 mile5KTrail

  from $15
• Thu26Nov

  Ten Trails Active Club 5k Turkey Trot

  Thu Nov 26 · 8:30 AM · Black Diamond · Eastside & South King

  5KTrail

  from $10

• Winter 2026-2741 races
• Spring 202734 races
• Summer 202715 races