Cambridge Half Marathon + 5K

About the Event

The Cambridge 5K is the kickoff to race weekend! It's a 3.1-mile course that starts and finishes at CambridgeSide. It's a quick out and back along the Charles River that will have you in awe of the Boston skyline.

The Cambridge Half Marathon is a 13.1-mile USATF certified course that starts and finishes at CambridgeSide. It is a fast and flat course along Memorial Drive featuring views of the Charles River, MIT, John W. Weeks Footbridge, Harvard University Stadium, and more.

Races Offered

Cambridge 5K

Oct 31, 2026

straighten

Distance — 5K

terrain

Type — Running

timer

10:00

sell

$45.00

Cambridge 5K Charity Runner

Oct 31, 2026

straighten

Distance — 5K

terrain

Type — Running

timer

10:00

sell

$45.00

Cambridge Half Marathon + 5K Challenge

Oct 31, 2026

straighten

Distance — Cambridge Half Marathon + 5K Challenge

terrain

Type — Running

timer

10:00

sell

$175.00

Cambridge Half Marathon + 5K Challenge Charity Runner

Oct 31, 2026

straighten

Distance — Cambridge Half Marathon + 5K Challenge Charity Runner

terrain

Type — Running

timer

10:00

sell

$175.00

Cambridge Half Marathon

Nov 01, 2026

straighten

Distance — 13.1 Miles

terrain

Type — Running

timer

07:00

sell

$100.00

Cambridge Half Marathon Charity Runner

Nov 01, 2026

straighten

Distance — 13.1 Miles

terrain

Type — Running

timer

07:00

sell

$100.00

Weather History

These values represent the 3-year monthly averages for October in Cambridge.

thermostat Temperature

8.7° / 17.6°

wb_sunny Feels like

5.6° / 15.0°

light_mode Avg sunshine hours

8h 25m

water_drop Avg rainfall

2.4 mm

ac_unit Avg snowfall

—

air Avg wind speed

12.0 km/h (Gentle breeze)

opacity Sweat loss rate

Low

terrain Course conditions

Firm and slightly soft

sunny Max UV Index

Moderate (4.0)

humidity_mid Humidity

74.0%

wb_twilight Sunrise

06:58

nightlight Sunset

18:01

About Cambridge

Learn more about the host city, Cambridge.

Cambridge is a city in Massachusetts, across the Charles River from Boston. It is renowned as the home of Harvard University and the Massachusetts Institute of Technology (MIT), both widely considered to be among the best universities in the world. The city's population was 118,000 in 2020; the fourth largest in the state.