Somerville Monster Dash Youth Races & 5K
Sunday, October 25, 2026, 10:30 AM · Baxter Riverfront Park at Assembly Row · Somerville
Dress up for a morning of running by the Mystic River. Children 12 and under can join a 200-meter race at 10:30 AM or a timed half-mile race at 10:40 AM on a closed path around Baxter Riverfront Park. The main 5K starts at 11 AM. Youth participants receive goodies and treats, and costume prizes are part of the day. Youth race registration is currently $12.55 per race; the 5K is $39.05, including mandatory fees. Register through Race Roster. Race-day number pickup runs 9:30–10:30 AM at the start/finish area on Great River Road. The shirt-order deadline has passed. Assembly Row’s separate Trick-or-Treat for a Cause runs 1–3 PM afterward; it is not part of race registration.
- Where: Baxter Riverfront Park at Assembly Row, Great River Road, Somerville, MA 02145
- Ages: All Ages
- Website: https://raceroster.com/events/2026/129907/somerville-monster-dash-5k