100 mile ultra runs
The longest of the ultra distances, 100 mile ultra marathons are a big challenge for any runner. But distance isn't always the key challenge with long ultra runs - the total ascent gives a much better indication of how hard it will be. Select your location to find 100 mile ultra runs in your area or scroll down to browse events coming up.
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Map view100 mile ultra runs in 2025/2026
Featured events are listed below - select a month/region or the map view to see all events.
- Sat 23 May 2026
- £163-£165
Farmmageddon | 100 Miles
Can you survive Farmmageddon? Held over 32-hours, runners will cover the fantastic 5.3K loop through the lovely grounds of Hyde Hall Farm and receive a t-shirt, buckle and medal to prove it!
- 100 miles trail running + 164 ft ascent
- Sat 25 Jul 2026
- £330
Rat Race 100 Ultramarathon
The 100-mile ultra for people who don't do 100-mile ultramarathons. Walk or run from Bamburgh Castle to Edinburgh Castle within 48 hours, fully supported.
- 100 miles trail running + 4853 ft ascent
100 mile ultra runs near you
Select your location for 100 mile ultra marathons in your area.