London Marathon: Elevation Profile, Course Map & Pace Calculator
Last Sunday of April · Fast, with only modest elevation change · 120 m total ascent
From Greenwich Park to Buckingham Palace, mostly flat, with a small dip under Tower Bridge at halfway. The course's elite field has produced several men's and women's world records, and the public ballot makes this the world's hardest mass-participation race to enter.
The London Marathon is fast, with only modest elevation change — rated 2/5 on our difficulty scale. Over the official 42.195 km (26.2 mi) the course gains about 410 ft (120 m) and loses 520 ft (160 m), with a net drop of 33 m (108 ft). Grade-adjusted pace says the toughest stretch arrives at kilometre 20 (near mile 12.5), demanding about 3% more effort than the same distance on flat ground. The steepest pitch on course reaches 4.6%.
Course stats
| Distance | 26.2 mi (42.195 km) |
|---|---|
| Location | London, United Kingdom |
| Total ascent | 410 ft (120 m) |
| Total descent | 520 ft (160 m) |
| Elevation range | 52 m (170 ft) |
| Net elevation | -108 ft (-33 m) |
| Steepest grade | 4.6% |
| Difficulty | 2/5 |
| Field size | ≈50,000 runners |
| Race day | Last Sunday of April |
| Elevation from | EA LIDAR Composite DTM (GB, 1 m) |
Bare-earth terrain model, smoothed over 500 m — it measures the ground, not the rooftops.
Key segments
| km 0–10 | Start to 10K. Net downhill, 30 m (+30 / −60 m), about 2% easier than flat. |
|---|---|
| km 10–21.1 | 10K to halfway. Rolling (+35 / −35 m). |
| km 21.1–30 | Halfway to 30K. Rolling (+30 / −25 m). |
| km 30–42.2 | 30K to the finish. Rolling (+30 / −35 m). |
Kilometre-by-kilometre splits (grade-adjusted)
Grade-adjusted (GAP) splits for a 4:00:00 finish, computed from the course's elevation profile with the Minetti gradient-cost model: uphill kilometres get more time, downhills less, at even effort. Splits scale proportionally for any other goal time — the interactive pace calculator on this page computes them exactly.
| Kilometre | GAP pace /km | GAP pace /mi | Elev Δ | Elapsed |
|---|---|---|---|---|
| 1 | 5:53 | 9:28 | +18 ft (+5 m) | 5:53 |
| 2 | 5:48 | 9:21 | +10 ft (+3 m) | 11:41 |
| 3 | 5:46 | 9:17 | +6 ft (+2 m) | 17:27 |
| 4 | 5:32 | 8:55 | -18 ft (-6 m) | 22:59 |
| 5 | 4:54 | 7:53 | -93 ft (-28 m) | 27:53 |
| 6 | 5:28 | 8:47 | -30 ft (-9 m) | 33:21 |
| 7 | 5:40 | 9:07 | -5 ft (-1 m) | 39:01 |
| 8 | 5:39 | 9:05 | -7 ft (-2 m) | 44:39 |
| 9 | 5:43 | 9:12 | +1 ft (0 m) | 50:22 |
| 10 | 5:50 | 9:23 | +13 ft (+4 m) | 56:12 |
| 11 | 5:37 | 9:02 | -10 ft (-3 m) | 1:01:49 |
| 12 | 5:44 | 9:13 | +2 ft (+1 m) | 1:07:33 |
| 13 | 5:37 | 9:02 | -10 ft (-3 m) | 1:13:10 |
| 14 | 5:51 | 9:24 | +14 ft (+4 m) | 1:19:00 |
| 15 | 5:41 | 9:08 | -3 ft (-1 m) | 1:24:41 |
| 16 | 5:40 | 9:08 | -4 ft (-1 m) | 1:30:21 |
| 17 | 5:44 | 9:14 | +3 ft (+1 m) | 1:36:05 |
| 18 | 5:40 | 9:08 | -5 ft (-1 m) | 1:41:45 |
| 19 | 5:41 | 9:08 | -3 ft (-1 m) | 1:47:26 |
| 20 | 5:44 | 9:13 | +1 ft (0 m) | 1:53:10 |
| 21 | 5:53 | 9:28 | +17 ft (+5 m) | 1:59:03 |
| 22 | 5:46 | 9:17 | +6 ft (+2 m) | 2:04:49 |
| 23 | 5:35 | 8:58 | -14 ft (-4 m) | 2:10:23 |
| 24 | 5:38 | 9:04 | -8 ft (-2 m) | 2:16:01 |
| 25 | 5:42 | 9:11 | -2 ft (-1 m) | 2:21:44 |
| 26 | 5:40 | 9:07 | -5 ft (-1 m) | 2:27:23 |
| 27 | 5:43 | 9:13 | +2 ft (+1 m) | 2:33:07 |
| 28 | 5:47 | 9:18 | +7 ft (+2 m) | 2:38:54 |
| 29 | 5:44 | 9:14 | +3 ft (+1 m) | 2:44:38 |
| 30 | 5:53 | 9:28 | +18 ft (+5 m) | 2:50:31 |
| 31 | 5:35 | 8:59 | -14 ft (-4 m) | 2:56:06 |
| 32 | 5:41 | 9:08 | -4 ft (-1 m) | 3:01:46 |
| 33 | 5:42 | 9:11 | 0 ft (0 m) | 3:07:29 |
| 34 | 5:51 | 9:24 | +14 ft (+4 m) | 3:13:19 |
| 35 | 5:45 | 9:15 | +4 ft (+1 m) | 3:19:04 |
| 36 | 5:39 | 9:05 | -7 ft (-2 m) | 3:24:43 |
| 37 | 5:50 | 9:23 | +13 ft (+4 m) | 3:30:33 |
| 38 | 5:32 | 8:55 | -19 ft (-6 m) | 3:36:05 |
| 39 | 5:37 | 9:03 | -9 ft (-3 m) | 3:41:43 |
| 40 | 5:44 | 9:13 | +2 ft (+1 m) | 3:47:27 |
| 41 | 5:47 | 9:18 | +7 ft (+2 m) | 3:53:13 |
| 42 | 5:38 | 9:05 | -7 ft (-2 m) | 3:58:52 |
| 42.2 | 5:50 | 9:24 | +3 ft (+1 m) | 4:00:00 |
Frequently asked questions
Is the London Marathon flat or hilly?
The London Marathon is fast, with only modest elevation change (2/5 difficulty). Total ascent is about 410 ft (120 m) over 26.2 miles.
How much elevation gain does the London Marathon have?
About 410 ft (120 m) of total ascent and 520 ft (160 m) of descent, for a net change of -108 ft (-33 m). Elevation is sampled from EA LIDAR Composite DTM (GB, 1 m) and smoothed over 500 m, so it will not match a GPS watch step for step.
What is the hardest part of the London Marathon course?
Kilometre 20 (near mile 12.5) is the toughest split on the course by grade-adjusted effort. Grade-adjusted pace puts it at roughly 3% more effort than flat running. The steepest grade on course is 4.6%.
How long is the London Marathon?
42.195 km (26.2 miles), the standard marathon distance. Certified courses are measured along the shortest legal line with a small safety margin, so a GPS watch usually reads a few hundred metres long — you run wider than the measured line, and GPS adds error of its own. Pace off the course markers rather than your watch's distance in the closing kilometres.
When is the London Marathon?
The London Marathon is typically held on the last Sunday of April. The next edition is expected around April 25, 2027. Confirm the exact date on the official race website.
How many runners take part in the London Marathon?
The field is roughly 50,000 runners.
What pace do I need to run the London Marathon in my goal time?
At an even pace: 3:00:00 needs 6:52/mi (4:16/km); 3:30:00 needs 8:01/mi (4:59/km); 4:00:00 needs 9:09/mi (5:41/km); 4:30:00 needs 10:18/mi (6:24/km); 5:00:00 needs 11:27/mi (7:07/km); 5:30:00 needs 12:35/mi (7:49/km). On this course, grade-adjusted pacing shifts a few seconds per mile between uphill and downhill splits — the pace calculator on this page computes those splits for any goal time.
Plan your London race
Courses like this one
- Toronto Marathon — 2/5 difficulty, 380 ft (120 m) ascent
- Honolulu Marathon — 2/5 difficulty, 440 ft (140 m) ascent
- Barcelona Marathon — 2/5 difficulty, 350 ft (110 m) ascent
How London Marathon ranks
- Flattest marathon courses — ranked 14 of 20 (410 ft (120 m) of climbing)
- Hilliest marathon courses — ranked 19 of 20 (410 ft (120 m) of climbing)
- Net-downhill marathon courses — ranked 10 of 13 (110 ft (30 m) net drop)
- Hardest marathon courses — ranked 19 of 20 (2/5 — 410 ft (120 m) up, 520 ft (160 m) down)
- World Marathon Majors compared — ranked 4 of 7 (410 ft (120 m) of climbing)
- Biggest marathons by field size — ranked 5 of 20 (≈50,000 runners)
Official race site: https://www.tcslondonmarathon.com/