Tough Guy claims to be the world’s most demanding one-day survival ordeal.
First staged in 1987, the Tough Guy Challenge is held on a 600-acre (2.42 square km) farm in Perton, Staffordshire, near Wolverhampton, England, and is organised by Billy Wilson (using the pseudonym “Mr. Mouse”). It has been widely described as “the toughest race in the world”, with up to one-third of the starters failing to finish in a typical year.
more here: [url deleted]