Mystic River Run

July 23 | 7:45 AM

Mystic River Reservation


A fun summer race, 3.1 Mile or 5 Mile road race around the Mystic River Reservation on July 23. The USATF-sanctioned course is around a beautiful river surrounded by trees and parks.


3.1 mile Pass

5 mile Pass

Registration will close at 2 PM on Friday, July 21.


BIB Pickup

Saturday, July 22nd (11 AM – 4 PM)
@ Marathon Sports Cambridge (1654 Massachusetts Ave, Cambridge, MA 02138)



Please consider selecting a $5.00 Donation in your registration. It will benefit our Youth Program. As a Thank You, we’ll give you a pair of Feature Socks.



7:00 AM – Number Pick-Up Opens
7:45 AM – 5 Miler Starts
9:00 AM – 3.1 Mile Starts
10:00 AM – Award Ceremony
10:15 AM – Course Closes



3.1 Mile Course 5 Mile Course



Please use Google Maps and either of these two locations for directions:

“Torbert MacDonald State Park” or “Station A-4, SP Medford”

There is plenty of parking, but please arrive early to allow time for parking, getting ready for the race etc.


Do not check any valuables. Although we will do our best to ensure that your gear is waiting for you at the end of the race, we are not responsible for lost items and/or gear check bags.


There are restrooms available in the ice rink. Please respect the surroundings to ensure we are able to continue using the park as our home base.

Team Competition

Running Clubs accumulate points for this race based on participation and finishing places. The year’s top clubs are honored and receive special awards at BRR’s Annual Runner’s Night.

COED Competition

Teams of 4, only for the 5 mile race
(2 Females & 2 Males)
First Place: Party with Beer & Food


Are you interested in volunteering for this race? Sign up for a position on the Volunteer page:
Sign Up to Volunteer.

Race FAQs

Baggage, Security, and Lost & Found
Number Pickup
Race Timing
Rules of Competition
Code of Conduct


Marathon Sports Gift Certificates will be given to the top three female and male finishers as determined by gun times.

Prizes given to age groups for top female & male:

19 years old and younger 50-59 years old
20-29 years old 60-69 years old
30-39 years old 70 years old and older
40-49 years old



The following is a close approximation of how the race fee is allocated in BRR’s service plan.

Cost Service Details
20% Community Initiative Covers BRR’s community programs, including two weekly run clubs, fitness challenges, summer activities, and marathon training programs
20% Youth Initiative Funds the Youth Initiative’s projects, including the Youth Access program to provide discounted registration for under-18 & Scholarship Fund
10% Non-profit Operations Contributes to overhead costs, expenses associated with management and operations
5% Permit Fees Contributes to fee for permits, insurance, and USA Track & Field fees
15% Security & Staff Contributes to compensation for park rangers, police, and personnel
20% Road Race Expenses Photographers, race equipment, race supplies, water, food, portable restrooms, etc.
10% Timing Expenses Contributes to cost for timing services





In-Kind Sponsor