TCS London Marathon

Why this race belongs on a competitive runner's shortlist

London suits destination marathon runners who want crowd support and a course they can prepare for in detail. Crossing Tower Bridge near halfway and finishing on The Mall give the race two clear landmarks, while the largely flat route makes a measured effort plan useful. The opening descent can tempt you into spending too much energy. For 2027, the race spans April 24 and 25 on the same course, with different finishing-time constraints by day.

Course overview

The 42.195 km route starts in Blackheath and Greenwich Park and finishes on The Mall. Separate start routes join in Woolwich before the course heads west past Cutty Sark, through Rotherhithe and over Tower Bridge. It then loops east through Docklands and Canary Wharf before returning along Victoria Embankment and Birdcage Walk. The opening loses height; later miles have smaller rises, underpasses and turns.

0 to 3 miles: Blackheath to Woolwich

The start routes join near mile 3 in Woolwich after the opening from Blackheath and Greenwich Park. The organizer describes this stretch as net downhill, with a descent around mile 3. Let gravity help without lengthening your stride or weaving for a faster split. The first water station is at mile 3; choose a clear approach and keep any early fueling consistent with your training.

3 to 14 miles: Cutty Sark and Tower Bridge

Pass Cutty Sark between miles 6 and 7, continue through Rotherhithe and cross Tower Bridge near halfway. The organizer calls miles 4 to 14 relatively flat with a small net drop, but flags the approach to the bridge as an incline. Hold effort up that rise. Water is at miles 6, 9, 12 and 14, Lucozade Sport at mile 7 and gels at mile 13.

14 to 20 miles: Docklands and Canary Wharf

The Docklands loop passes the Westferry Underpass and Canary Wharf. RoutePrinter's modeled profile puts this interval at roughly 2.2 m to 12.4 m above sea level, with small local changes. Buildings and the underpass can disturb GPS, so use mile markers to check pace. Water is at miles 16, 18 and 20, Lucozade Sport at mile 15 and gels at mile 19; fuel before fatigue makes the turns harder.

20 miles to 26.2 miles: Embankment to The Mall

Return along The Highway toward Tower Hill and Victoria Embankment, then turn by Westminster Bridge and follow Birdcage Walk to The Mall. RoutePrinter's modeled late profile ranges from roughly 4.2 m to 12.6 m, ending near 6 m. This is a low, mildly changing finish rather than a major climb. Water at miles 22 and 24 and Lucozade Sport at miles 21 and 23 support your practiced closing plan.

Elevation checkpoints and how to read them

RoutePrinter gives 417 ft, or 127.1 m, of modeled total ascent for its stored April 2026 route. Its modeled start and finish heights imply about 35 m of net descent, which is a separate measure from cumulative climbing. The organizer identifies the downhill opening and the short rise before Tower Bridge. Later changes are smaller, including the Westferry Underpass. These estimates are a course reference, not an organizer-certified 2027 survey.

Aid stations and race-day logistics

The current course page lists water at miles 3, 6, 9, 12 and every 2 miles through mile 24, Lucozade Sport at 7, 15, 21 and 23, gels at 13 and 19, and refills at 5, 10, 14, 17 and 20. For start travel, the 2026 guide assigns Blackheath station to Blue, Green and Yellow starts, Maze Hill to Pink, and Greenwich to Red. Those are historical train-access references; 2027 assignments and bag-drop rules are not yet confirmed in the guide. Saturday 2027 closes The Mall finish at 17:30, so check your allocated day.

Practical pacing plan

Control speed on the opening descent instead of banking time. Hold effort on the Tower Bridge approach, then check your average pace against the course markers around Canary Wharf. If your stride remains steady after Tower Hill, increase effort toward Birdcage Walk and save the final push for The Mall. Wind between Docklands buildings or a warm April day makes even this low route harder; ease the pace target when the effort rises.

Historical weather pattern

April weather history around London shows typical daily temperatures of 38.5 to 61.8 F, daily mean winds of 4.4 to 12.7 mph, and at least 1 mm of precipitation on 31 percent of days. Conditions can change, so check the race-week forecast before travel and again on race morning.

Edition history