The historic course starts on Main Street in the rural New England town of Hopkinton and follows Route 135 through Ashland, Framingham, Natick, and Wellesley to where Route 135 joins Route 16. It continues along Route 16 through Newton Lower Falls, turning right at the fire station onto Commonwealth Avenue, which is Route 30. It follows Commonwealth through the Newton Hills, bearing right at the reservoir onto Chestnut Hill Avenue to Cleveland Circle. The route then turns left onto Beacon Street continuing through Kenmore Square, and under Massachusetts Avenue. The course turns right onto Hereford Street then left onto Boylston Street, finishing near John Hancock Tower in Copley Square. This race is traditionally held on Patriot's Day in April, and for the 2021 edition, the event will be held on Monday 11th October 2021.