Boston Marathon 2027 : the course km by km, race week and travel

Boston is a race that runs downhill and is still hard. The finish is 136.6 m lower than the start, but most of that height is gone in the first 6 km, and the course still climbs about 105 m in all, the hardest of it in the Newton hills after km 25. Runners who bank time on the early descent pay for it on Heartbreak Hill. The other thing that makes Boston different is the clock: the start is a bus ride away from the city and the waves go off between 10am and the late morning, so the morning is long before the first step.

The course is point to point, along one road for most of its length. In the B.A.A.’s own words it starts on Main Street in Hopkinton and follows Route 135 through Ashland, Framingham, Natick and Wellesley, then Route 16 through Newton Lower Falls, then Commonwealth Avenue through the Newton hills and Beacon Street into Boston. The kilometres and heights below are measured along that street list, walked onto OpenStreetMap, on the USGS elevation model. No 2027 course change has been announced, but check the organiser’s course page before race week.

Km 0 to 6: the drop out of Hopkinton

The start is on Main Street in Hopkinton at 140.5 m, and East Main Street falls straight away. By km 1.2 the road has lost 32 m, and by km 5.9 it is at 58.5 m: 82 m down, 60% of the whole race’s net drop, in under 6 km. Water and Gatorade come at every mile from mile 2 (km 3.2). This is the stretch that decides how the last 10 km feel. The descent makes a goal pace feel easy, and the quadriceps take the bill. Start slower than you think you need to.

Km 6 to 19: Route 135 through Ashland, Framingham and Natick

From km 6 the course settles onto Route 135 as Union Street, Waverly Street, then West and East Central Street, and for most of the next 18 km the road rolls between 41 m and 64 m. There are small rises, about 9 m around km 7 and about 12 m between km 15.4 and km 18.4, and long easy stretches between them. This is the place to find a rhythm and stay in it.

Km 19 to 25.7: Wellesley, halfway and Newton Lower Falls

The Wellesley town line comes at mile 11.8 (km 19.0), with the first of three Maurten Hydrogel stations, and Central Street takes the course through the town. Wellesley College students, by tradition, cheer the runners as they pass. Halfway falls on Central Street, at km 21.1. Washington Street, Route 16, picks up at about km 21.4 and runs through Newton Lower Falls, and the road drops from about 49 m at km 24.3 to the course’s low point before the hills, 19.7 m at about km 25.7.

Km 25.7 to 33.6: the Newton hills and Heartbreak Hill

From that dip the road climbs 48.7 m in 7.9 km to 68.4 m at about km 33.6, an average of only 0.6%. It comes in four rises, the four Newton hills, with short drops between them. The first lifts the road about 10 m around km 26. At about km 28.2 the course turns right at the Newton fire station onto Commonwealth Avenue, Route 30, and the second rise follows. A Maurten station sits at mile 17 (km 27.4) in Newton. The third climbs about 11 m between km 30.8 and km 32.6. The fourth is Heartbreak Hill, between the 20 and 21 mile marks near Boston College, and on the measured line it is the steepest: about 21 m from km 32.6 to the top at km 33.6. None of them is steep on paper. They hurt because they come after 25 km of mostly downhill running.

Km 33.6 to 40.6: down past Boston College and into Brookline

After the top the road falls 64.5 m over the last 8.6 km and gains only 3.3 m on the way. The third Maurten station is at mile 21.5 (km 34.6), just after Boston College. At about km 35.7 the course bears right at the reservoir onto Chestnut Hill Avenue to Cleveland Circle, and turns left onto Beacon Street at about km 36.0. Beacon Street runs 4.6 km through Brookline, and between about km 37.3 and km 39.1 it loses another 25 m, downhill running on legs that have just done the hills.

Km 40.6 to the finish: Kenmore Square and Boylston Street

The course reaches Kenmore Square, where the crowd is thick as runners enter the final mile, rejoins Commonwealth Avenue at about km 40.6 and passes under Massachusetts Avenue. At about km 41.5 it turns right onto Hereford Street, against the normal flow of traffic, and at about km 41.7 left onto Boylston Street. The last 485 m run straight down Boylston Street to the finish near the Boston Public Library in Copley Square, at 3.9 m above sea level.

The 2027 race-weekend programme is not out yet. What follows is how race weekend ran in 2026, from the B.A.A.’s athlete pages, and the 2027 rules where they are already published. Check the info for athletes page again in early 2027.

The expo and your bib

Bibs are collected at the expo at the Hynes Convention Center, 900 Boylston Street, on the same street as the finish, a few blocks west of it. In 2026 it was open on the Friday from 10am to 7pm, the Saturday from 9am to 7pm and the Sunday from 9am to 6pm, and the expo is free and open to the public. Bib pick-up is only possible during expo hours, and each participant must collect their own bib. Bring an official government-issued photo ID: photocopies and digital versions are not allowed. Your bib number and a digital number pick-up pass arrive by email in early April.

Buses to Hopkinton

The organiser recommends the official B.A.A. buses. They load on Charles Street between the Public Garden and Boston Common, and in 2026 each wave had its own loading time:

• Wave 1 (red bibs): buses from 6.45am, start 10am
• Wave 2 (white bibs): buses from 7.30am, start 10.15am
• Wave 3 (blue bibs): buses from 7.30am, start 10.28am
• Wave 4 (yellow bibs): buses from 8am, start 10.41am
• Wave 5 (green bibs): buses from 8am, start 11.01am
• Wave 6 (orange bibs): buses from 9am, start 11.21am

The last bus leaves Boston Common at 9.30am. Each wave has eight corrals, and your corral is printed in a box on your bib. The wheelchair, handcycle, professional and para starts go off between 9.06am and 9.50am. Parking for runners in Hopkinton is very limited.

Athletes’ Village and the start

The buses arrive at the Athletes’ Village, where you show your bib to enter, and where there is water, Gatorade and toilets. The start is a 0.7 mile (about 1.1 km) walk from the Village. Plan for a long wait: a Wave 1 runner on an early bus can spend more than three hours between Boston Common and the start line.

Gear check

Only the clear plastic gear bag the B.A.A. provides is accepted, and no bags travel from Hopkinton to Boston. Gear check is in Boston, before the buses: anything you carry to the Village and leave there does not come back, so take only old layers you can give up. In 2026 bags were picked up after the race around Boylston and Berkeley Streets, and the family meeting area was on Stuart Street between Berkeley and Clarendon Streets.

On the course

Water and Gatorade are at every mile from mile 2. There are three Maurten Hydrogel stations, at miles 11.8, 17 and 21.5, and 26 medical stations along the course. No official pacers are listed on the B.A.A.’s pages.

The cut-off

Under the 2027 rules, official timing stops at 5.30pm, about six hours after the last official starter crosses the line, and every entrant confirms they can finish in under six hours. Runners who finish later are not official finishers. The course reopens behind a pace of about 13:44 a mile, and the organiser has arrangements to assist runners at or slower than that pace.