London 100 Ultra Marathon | 25K

London 100 is Central London's ultramarathon. With 3 challenge distances (100km, 50km, and 25km), the event has distances for experienced ultramarathoners, and for those stepping up from marathons or half marathons. From a superb indoor Central London race HQ, four 25km routes explore north, south, east and west of the capital. Experience areas of London you never knew existed, discover the capital's hidden trails and enjoy the famous sights and landmarks of one of the world's greatest cities - all in one long run.