Decathlon Büyükada Half Marathon will be held in the magical beauties of Büyükada on October 19, 2025. Foreign national participants must click on the ‘Register’ button to complete their registration for the race. HIS Travel, as the official tourism agency of Decathlon Büyükada Half Marathon 2025, is the official affiliate of Decathlon Büyükada Half Marathon in all registration procedures of foreign participants.