Boston 5K Summer Series - Race 3
Cambridge, Massachusetts, United States
Sep 4, 2026 - Friday
5k, Fundraiser
Race Information
This 5k series takes place on eight Thursday evenings from April through September for fun, friendly, chip-timed 5K runs to kick cancer’s butt.
All races are held at the American Legion Marsh Post #442 in Cambridge, MA, and run on paths along the Charles River. Each event will include a post-race party at the Marsh Post with beer generously provided by Mighty Squirrel. 100% of the event proceeds go to charity, including a portion to the American Legion Marsh Post. RACE Cancer Foundation’s Boston 5K Summer Series also provides funding for the Sunscreen Squad, bringing free sunscreen to outdoor events across Massachusetts.
👍 Run Pick of the Month: Road of Rainbows
📍 Boston, MA - June 6, 2026
💸 SAVE 15% On Entry & Merch. Use Code: Runguides26
😄 Why We Like This Run
✅ Flat, flexible loop course perfect for all paces
✅ All participants receive a rainbow medal
✅ Post-race free concert
Celebrate Pride at Road of Rainbows, a high-energy 5K on Boston Common where self-expression takes center stage and costumes compete for a $1,500 “Best Dressed” prize. Whether you run, walk, or strut, this inclusive event blends fitness, community, and a vibrant post-race concert into one unforgettable day.
🏃 Training for This Race?
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🎁 2 weeks free for RunGuides runners
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Race Facts
Race Size: 100 - 500
Course Type: Road
Boston Qualifier: No
Kids Run: No
Where to Stay
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