Polaris Challenge Summer Race
Tweed Valley, Borders

This 80km course requires self-supported mountain biking for two days across wild countryside, with entrants locating and riding to as many checkpoints as possible.

Visit polarischallenge.com for details.

Edinburgh Rat Race
Edinburgh

Teams of three compete in this multi-discipline adventure race, which includes running, biking, kayaking, climbing and orienteering around the streets, fields and waterways of the Scottish capital.

Visit ratraceadventure.com for details.

Multi-Sport Trailathlon
Exmoor, Devon

If you’re looking to move on from triathlons (or just don't like swimming), this race is for you. With trail running, mountain biking and kayaking across stunning scenery, the three race formats – from Sprint totalling 10 miles, Lite at 20 miles or Classic at 30 miles – offer something for all abilities.

Visit endurancelife.com for details.

Bedford Multisports Weekender
Box End Park, Bedford

Entrants can choose from a range of events over the weekend, from 10km runs through to 4km kayak races and a triathlon, all at the Box End water ski park. Camping is also available for those competing on both days.

Visit galeforce-events.com for details.