Spectator Guide · Boulderthon

Boulderthon Spectator Guide

October 29, 2026 · 3 min read

Large race in Boulder. Base at the start/finish area.

In this guide

At a glance

Date
Sunday, September 26, 2027
Location
Boulder, CO
Distances
Marathon, Half Marathon, 10K, 5K, Kids Run
Field size
About 15,000 runners
Registration
boulderthon.org

The Boulderthon is a large field event in Boulder. Spectators should base at the start/finish area.

Best places to stand

  • Start/finish: Boulder start and finish area.
  • Course: sidewalks along the published route.

Getting there

Use the official parking and closure information. Arrive early.

Where to meet

Agree on a landmark outside the finish chute.

Keep exploring

Common questions

When is the Boulderthon?
Sunday, September 26, 2027.
How do I register for the Boulderthon?
Registration is handled by the organizer at boulderthon.org.