In the context of geographical exploration "Why explore?" is normally a loaded question, often put to you by someone who has already decided in their own mind that most if not all earthbound exploration has already been accomplished...
On 6 August 1497, almost precisely five years since Christopher Columbus had first set sail for the New World, his Venetian rival John Cabot navigated his tiny ship Matthew back up the River Avon to the English port of Bristol.
Over 80,000 people have registered, and paid a deposit, to express their interest in being part of a reality TV programme that aims to send a small number of people to Mars to establish the first colony there.
From looking into the eye of a whale shark as you scuba dive in the Indian ocean, to reaching the peak of Mount Kilimanjaro, or capturing the perfect photograph of Angkor Wat - adventure travel means something a little different for everyone.