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.
Featured events are listed below - select a month/region or the map view to see all events.
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!
Take on 100 historic miles across the beautiful Southern Upland Way - one of the greatest trails in the UK. Ultrarunners will tackle several ascents, pass through forests, valleys and by lochs.
Yr Wyddfa (Snowdon) is the highest mountain in England and Wales. Your challenge is to ascend and descend as many times as possible in 24 hours - solo or as a relay team.
Select your location for 100 mile ultra marathons in your area.