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4K Trail Run

Boston, United States • 20-21 May 2026

Event Overview

The 4K Trail Run is a trail running event held on Cathleen Stone Island in the Boston Harbor. The event takes place over two days and includes options for both individual runners and corporate teams.

Course & Location

The race is a 4-kilometer trail run that takes place on Cathleen Stone Island. Participants reach the island via a ferry ride, which takes approximately 30 minutes.

Schedule & Registration

The event is scheduled for Wednesday, May 20, 2026, and Thursday, May 21, 2026. Registration is available for the following event types:

  • Wednesday 4K Trail Run - Individual Registrations
  • Wednesday 4K Trail Run - Team Registrations
  • Thursday 4K Trail Run - Individual Registrations
  • Thursday 4K Trail Run - Team Registrations

The deadline for corporate team registration is May 1st, 2026. Individuals can also register on their own or start a team with friends.

Post-Race & Purpose

The event includes a post-race gathering with dinner and beer. Funds raised from the event support Cathleen Stone Island's mission to provide free, hands-on science learning programs for youth in Boston. Visit the organization's website for the most recent information.

United States Massachusetts Boston

Race information

Registration
Visit the organization's website for the most recent information.
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