4

100K ultra runs in London

Find 100k ultra runs in London in 2026/2027 - filter by date, location or category, display on a map or use the advanced search to find your perfect race.

Filter by place

Filter by date

Map

Event listings

Select an event for photos, video, route, location, reviews, entry fees and how to enter.

Walk, jog or run the capital-to-coast route with 2,000 other adventurers over a range of distance options available and superb support all the way, for all abilities and experience levels.
  • Sat 23 - Sun 24 May
  • £89-£199
Brighton, East Sussex, UK

London 2 Brighton Ultra Challenge

Walk, jog or run the capital-to-coast route with 2,000 other adventurers over a range of distance options available and superb support all the way, for all abilities and experience levels.

  • Trail run 3
  • Ultra run 2
  • Marathon
  • 100K ultra run 2
  • Families
  • Beginner-friendly
  • Entertainment
  • Event village
  • Age 14 & over
England’s greatest river provides a fantastic backdrop for an unforgettable 'festival' challenge weekend, with distances from 10km right up to 100km there’s a Thames Challenge for everyone!
  • Fri 11 - Sun 13 Sep
  • £39-£199
London, UK

Thames Path Ultra Challenge

England’s greatest river provides a fantastic backdrop for an unforgettable 'festival' challenge weekend, with distances from 10km right up to 100km there’s a Thames Challenge for everyone!

  • 100K ultra run 2
  • 50K ultra run 2
  • Trail run 4
  • Charity walk 4
  • Ultra run
  • + 1 more race
  • Families
  • Beginner-friendly
  • Entertainment
  • Music
  • Event village
  • Urban
  • Rural
  • Age 14 & over

Search options

Back to search options
4 steps to wellbeing
Sleep well

A good night's sleep is an essential foundation for a healthy lifestyle, effective training and weight control.

Train slow

Low-intensity training is easier for you, reduces the risk of injury and helps builds an efficient aerobic system.

Eat natural

Cut out sugar & junk food, reduce carbs, eat natural foods and train your body to burn fat for fuel.

Get outdoors

Fresh air, natural light and reconnecting with nature all help to improve mental and physical wellbeing.