Adventurer Sean Conway starts 'UK coastline triathlon'

Sean Conway is believed to be the first person to run, swim, sail and cycle the length of the UK.

An extreme adventurer has started a 4,000-mile ultra-triathlon around the coastline of Britain.

Sean Conway will use a bamboo bike and carry all his gear with him during what he predicted would be "the three toughest months" of his life.

He is already believed to be the first person to have run, swam, sailed and cycled the length of the UK.

The 34-year-old, from Cheltenham, began his challenge earlier at Lulworth Cove, Dorset.

He will cycle around the coast to Scarborough where he will leave his bike and run to Brighton. Once there he will begin his final leg and swim back to where he started.

Mr Conway completed an "ultimate triathlon" between Land's End and John O'Groats in May last year.

The bearded adventurer hopes to start and finish his challenge in Lulworth Cove in Dorset

Before starting out he said: "I was conscious of trying to up my game from the last few adventures I've done. I've done a long cycle independently, a long swim and a long run.

"I thought why not combine them all into some sort of epically big, ironman triathlon?

"Then I thought, well I love Britain, I love this island, it's got so much to offer, why don't I do one big one following the coastline?

"It's quite daunting, but I am as ready as I can be - you have just got to prepare as you go along.

"It gives me purpose and a reason to get out of bed in the morning. I want to inspire people, as most people can do a lot more than they think they can."

A documentary will air on the Discovery Channel later in the summer and his progress can be tracked the channel's website.

Mr Conway completed an "ultimate triathlon" between Land's End and John O'Groats in May last year