how long is the marathon race

A marathon race is exactly 26.2 miles or 42.195 kilometers long. More precisely, it is 26 miles and 385 yards (or 42,195 meters). This distance is standardized for all official marathon races worldwide. The specific length of 26.2 miles was established at the 1908 London Olympics to allow the race to start at Windsor Castle and finish in front of the royal box at the Olympic stadium. This distance was later adopted officially in 1921 by the International Amateur Athletic Federation (now World Athletics) and has been the standardized marathon distance ever since.