The marathon is a long-distance running event with an official distance of 42.195 kilometres (26 miles and 385 yards), that is usually run as a road race. The event was instituted in commemoration of the fabled run of the Greek soldier Pheidippides, a messenger from the Battle of Marathon, to Athens. The marathon was one of the original modern Olympic events in 1896, though the distance did not become standardized until 1921. More than 500 marathons are held throughout the world each year, with the vast majority of competitors being recreational athletes. Smaller marathons, such as the Stanley Marathon, can have just dozens of participants, while larger marathons can have tens of thousands of participants. The name Marathon comes from the legend of Pheidippides, a Greek messenger.
Contributions by KeithH, Wikibofh, and MisterHand.