Isle of Man TT: One hundred take on new triathlon
About 100 competitors are taking part in the Isle of Man's inaugural TT triathlon, which is under way in Douglas.
Participants will complete a 2.4 mile swim in Douglas Bay, a three-lap bike ride around the TT course, followed by a full marathon.
The course begins at the TT Grandstand and ends on Douglas Promenade.
Chief Marshal, Simon Slade said: "Athletes train for about nine months to be ready for a race like this."
He added: "Triathlons are incredibly popular because they test you in the fullest way possible - you have to be at peak fitness but you also have to have the stamina to pace yourself through the day.
"What we are hoping is that members of the public will come out and support the athletes.
"We'd like a bit of a party atmosphere with people standing by the side of the road to cheer on their friends and family."
Medical cover has been arranged throughout the day with paramedics, police and St John Ambulance on standby at various points around the course.
Race director Richard Wallace said: " Ever since I started organising triathlons many years ago I had always wanted to run an endurance event on the Isle of Man because of the legendary TT Course, coupled with the way in which the island and its communities embrace all forms of sport."