London 100

JUN
12
2027
Urban 100 km ultramarathon in central London with 100 km, 50 km and 25 km routes that pass 100+ city landmarks and include staffed checkpoints.
Sat 12 Jun 2027
100 kilometers 50 kilometers 25 kilometers

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London 100

London 100 is an urban-ultra event that starts and finishes from an indoor Run HQ in central London. The route is designed to showcase more than 100 of the city's landmarks and to explore north, south, east and west areas of the capital across linked 25 km sections.

The event offers three challenge distances:

  • 100 km ultramarathon
  • 50 km ultramarathon
  • 25 km EAST route
  • 25 km WEST route

Four 25 km route sections form the full course layout, with route checkpoints positioned at the start and the middle of each 25 km section. Checkpoints are stocked with water, snacks and fruit. Organisers provide a training plan, charity running options and volunteer opportunities. The central London location is intended to make the event more accessible for arrival and departure and for supporters to reach multiple parts of the course.

Time limits are specified for completion of each distance. The event is presented as an urban ultramarathon that runs through a variety of city streets, trails and notable landmarks, with an indoor Run HQ serving as the event base. Visit the organization's website for the most recent information.

100 km
London 100 - 100km Ultramarathon
50 km
London 50 - 50km Ultramarathon
25 km
London 25 - 25km West Route
25 km
London 25 - 25km East Route
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