London Marathon
Race Day Weather
Cool start, gradual warming
Runners will face a temperature rise from 51°F at the start to 58°F by the finish, with average humidity at 64%. Wind will be a light crosswind early, shifting to beneficial tailwinds between miles 2-3 and 10-20, while headwinds will appear from miles 5-7 and 11-12. Runners should adjust their pace conservatively during the headwind sections and stay hydrated as they navigate the rolling terrain.
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Race Info
The London Marathon starts from three lines on Blackheath and in Greenwich Park and finishes on The Mall by Buckingham Palace, passing the Cutty Sark near mile six and crossing Tower Bridge close to halfway on a net downhill course. Sabastian Sawe set the men's world record of 1:59:30 there in 2026, the first sub-two-hour time in a record-eligible marathon, and Tigst Assefa set the women-only world record of 2:15:41 the same day. It's one of the seven Abbott World Marathon Majors, held on a Sunday in late April, and its 2025 edition set a Guinness World Record with 56,640 finishers.
Race Day Tips
Expect heavy congestion at the start, especially around Greenwich. Be prepared to navigate through slower runners for the first couple of miles, as the narrow streets can make it challenging to maintain your desired pace.
The downhill start can lead to a faster pace than intended. Be cautious during the first few miles to avoid burning out early, as the downhill can trick you into running too fast.
Consider holding back your pace until after Canary Wharf around mile 18, where the crowds can be overwhelming but also energizing. This is a good point to assess your energy levels and decide if you can push harder for the final stretch.
Expect heavy congestion at the start, especially around Greenwich. Be prepared to navigate through slower runners for the first couple of miles, as the narrow streets can make it challenging to maintain your desired pace.
The downhill start can lead to a faster pace than intended. Be cautious during the first few miles to avoid burning out early, as the downhill can trick you into running too fast.
Consider holding back your pace until after Canary Wharf around mile 18, where the crowds can be overwhelming but also energizing. This is a good point to assess your energy levels and decide if you can push harder for the final stretch.
Tips from runner race reports
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Reviews & Race Reports
Incredible crowd support and a fast course. Watch your pacing early to avoid cramping later!
Crowd Energy — The crowd support is electrifying throughout the course. Runners mention feeling an incredible boost, especially around iconic spots like Big Ben and Canary Wharf. Many found the cheers helped them push through tough moments, particularly in the final miles.
Navigating the Start — Expect a congested start. Many runners felt penned in for the first few kilometers, making it tough to find a rhythm. Arrive early to avoid stress and give yourself time to settle in.
Hydration Strategy — Several runners struggled with hydration, especially those who didn't plan ahead. Make sure to practice your fueling strategy in training, as some experienced digestive issues from gels on race day. Don’t skip water stations, even if you feel fine early on.
Pacing Challenges — The course can feel deceptively fast at the start due to slight downhill gradients. Many runners noted the importance of pacing conservatively to avoid hitting the wall later. Pay attention to your effort levels after 20 miles, as fatigue can sneak up on you quickly.
Enjoyed the crowd but struggled with heat and endurance after 25K
I ran pretty consistent and conservative splits for the first 10K and lapped my watch every 5K. At that point I realized it wouldn't be a PB-day with the heat and just decided that I would try and finish strong. I already hit the main goal of showing up to the race able to run.
Struggled with heat and anxiety, but finished under 2:50
When it finally got to 9.20 and the wave pen opened, the sun was beating down with no shade and I couldn't shake a feeling of tight chestedness. My HR was 110-120, way above my normal 60-70. I hoped that I'd ease into the race when it started. I simply couldn't relax into the race. I knew holding 3:55 shouldn't be difficult but every step felt like a real battle.
Ran for vibes, not time, and loved every moment of it
I knew I wouldn't have my legs to count on for these 26.2 miles and I'd made peace with that. Every time it hurt, I'd just tell myself "well, you knew this was going to hurt". The energy I didn't have in my legs I had in my heart. I high-fived every kid, I petted every dog, I danced to every DJ, I screamed at EVERYONE to make them scream at me.
Felt strong in the final stretch, fastest finish ever
Finally my/our luck came good. The weather forecast for Sunday 21st was pretty excellent by recent standards. 8C (46F) at the start, with a North-easternly wind. The most common wind (Westernly) leaves you running into a headwind for the majority of the race, including the final 6 mile stretch.
Stuck with the pacers, surged at the end for a sub-3 finish
Caught back up to the Pace group around 40KM mark, which we hit at 2:49:52 point. 10 mins to hit 2.195 KM left me feeling great. Made the right passed Big Ben right before the 41KM mark just under 2:54. Goal was within reach, needed to hold it together for another 5 mins or so. Hit the 600M and 400M to go marks next to St James Park feeling great. Passed the pacer in the last 200M (to be fair, he had slowed down to encourage people from the pack to finish). Crossed the line in 2:59:08, mission accomplished!