When the marathon comes to town, prepare yourself for crazy costumes, famous faces, record attempts and dramatic moments. And even if you're not running the race, you can still enjoy the atmosphere from afar.
Kenyan athletes Eliud Kipchoge and Jemima Sumgong won the elite races, with Sumgong taking the top spot (two hours, 22 minutes and 58 seconds) despite a fall earlier in the race, while Kipchoge broke his own record (two hours, three minutes and four seconds) and was just seven seconds short of the world record.
Among the celebrities running the course were Game of Thrones star Natalie Dormer, Top Gear host Chris Evans and Dame Kelly Holmes.
Meanwhile, in space, British astronaut Tim Peake ran the equivalent distance on a treadmill in around an out of this world, three hours and 35 minutes.
Take a look at the gallery below for some of the best outfits and faces in the race.