Ironman triathlons in the UK
An Ironman or full distance triathlon is one of the toughest event formats around and only do-able by the most committed athletes with both the physical and mental endurance to cross the finish line. Also called a 140.6 triathlon or full distance triathlon, these long-distance events involve a 2.4-mile swim (3.9km), a 112-mile bike ride (180km), and a 26.2-mile run (42.2km) - a total of 140.6 miles completed in an average of around 10-15 hours. Select your location for full distance triathlons in your area or scroll down to see major events coming up.
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Full distance triathlons in 2025
Featured events are listed below - select a month/region or the map view to see all events.
- Sun 31 Aug
- £250
Roadford Lake Triathlon | Iron Distance
Brand new to the popular Roadford Lake Tri, the Iron Tri has a superb swimming venue with quiet rolling roads for the bike course and a cracking run too. Plus there's lakeside camping available too.
- 3.8 km lake swimming
- 185 km road cycling + 4245 ft ascent
- 42 km road running + 1073 ft ascent
Ironman triathlons near you
Select your location for Ironman and 140.6 triathlons in your area.