5

100K ultra runs in London

Find 100k ultra runs near me in London for 2025/2026 - search by date or place, display on a map or use the advanced search to find your perfect race.

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Leafy Richmond to sunny Brighton – over the North Downs and the South Downs, with some wonderful Surrey and Sussex countryside in between, fully supported all the way with a huge celebratory finish!
  • Sat 24 May
  • £199
  • 14 charities
  • Sat 24 May
  • £199
  • 14 charities
Richmond, UK

London 2 Brighton Ultra Challenge | Full 100km Continuous

Leafy Richmond to sunny Brighton – over the North Downs and the South Downs, with some wonderful Surrey and Sussex countryside in between, fully supported all the way with a huge celebratory finish!

  • Chip timing
  • Enter online
  • GPS tracking
  • Hilly
  • Age 18 & over
  • 100 km trail running + 1500 m ascent
Leafy Richmond to sunny Brighton, over the North and South Downs, with some wonderful Surrey and Sussex countryside - all in daylight hours and with a good nights' sleep mid-way!
  • Sat 24 - Sun 25 May
  • £199
  • 14 charities
  • Sat 24 - Sun 25 May
  • £199
  • 14 charities
Richmond, UK

London 2 Brighton Ultra Challenge | Full 100km over 2 days

Leafy Richmond to sunny Brighton, over the North and South Downs, with some wonderful Surrey and Sussex countryside - all in daylight hours and with a good nights' sleep mid-way!

  • Chip timing
  • Enter online
  • GPS tracking
  • Undulating
  • Hilly
  • Age 18 & over
  • 100 km trail running + 1500 m ascent
The full, non-stop option of the Thames Path Challenge from leafy South West London following the river to Hampton Court, Runnymede to finish at Henley-on-Thames for a celebratory finish and BBQ.
  • Sat 13 - Sun 14 Sep
  • £199
  • 12 charities
  • Sat 13 - Sun 14 Sep
  • £199
  • 12 charities
London, UK

Thames Path Ultra Challenge | Full 100km Continuous

The full, non-stop option of the Thames Path Challenge from leafy South West London following the river to Hampton Court, Runnymede to finish at Henley-on-Thames for a celebratory finish and BBQ.

  • Chip timing
  • Enter online
  • GPS tracking
  • Flat
  • Undulating
  • Age 18 & over
  • 100 km trail running + 350 m ascent
The full distance option of the Thames Path Challenge over 2 days with 50km on day 1 and 50km on day 2, meaning you experience the route in daylight with the chance to sleep overnight.
  • Sat 13 - Sun 14 Sep
  • £199
  • 12 charities
  • Sat 13 - Sun 14 Sep
  • £199
  • 12 charities
London, UK

Thames Path Ultra Challenge | Full 100km over 2 days

The full distance option of the Thames Path Challenge over 2 days with 50km on day 1 and 50km on day 2, meaning you experience the route in daylight with the chance to sleep overnight.

  • Chip timing
  • Enter online
  • GPS tracking
  • Undulating
  • Age 18 & over
  • 100 km trail running + 350 m ascent
  • Sat 10 May
London, UK

London 100 Ultra Marathon | 100K

  • 100 km trail running

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