The Royal Marsden Cancer Charity

Whether you’re still a bit of a running newbie or a total tarmac addict, the Semi-Marathon is just the right length. That’s why over 40,000 people register every year to pound the streets of the world’s fashion capital… in neon trainers.

21.1km is a distance that shows real athletic ambition, which will be illustrated by the photo of you at the finish line, looking totally worn-out. You’ll still post it on the social networks, of course: it must be the only time that sweat will earn you likes!