An Ironman Triathlon is one of a series of long-distance triathlon races organized by the World Triathlon Corporation (WTC), consisting of a 2.4-mile (3.86 km) swim, a 112-mile (180.25 km) bicycle ride and a marathon 26.22-mile (42.20 km) run, raced in that order. It is widely considered one of the most difficult one-day sporting events in the world.
Most Ironman events have a limited time of 16 or 17 hours to complete the race, course dependent. The race typically starts at 7:00am; the mandatory swim cut off for the 2.4-mile (3.86 km) swim is 9:20am (2 hours 20 minutes), the mandatory bike cut off time is 5:30pm (8 hours 10 minutes), and the mandatory marathon cut off is midnight (6 hours 30 minutes). Any participant who manages to complete the triathlon within these time constraints is designated an Ironman.
The name “Ironman Triathlon” is also associated with the original Ironman triathlon which is now the Ironman World Championship. Held in Kailua-Kona, the world championship has been held annually in Hawaii since 1978 (with an additional race in 1982). Originally taking place in Oahu, the race moved to Kailua-Kona in 1981, where it continues today. The Ironman World Championship has become known for its grueling length, harsh race conditions, and Emmy Award-winning television coverage.
Other races exist that are of the same distance as an Ironman triathlon but are not produced, owned, or licensed by the World Triathlon Corporation. Such races include The Challenge Family series’ Challenge Roth and the Norseman Triathlon.
Reproduced from: Wikipedia the Free Encyclopedia