The distance of a marathon is 42.195 kilometers (or 26.2 miles). But why is it set at that distance? Why not 40 km, 50 km or 25 miles?

The origin of the marathon

The origin of the marathon can be traced back to ancient Greece. According to legend, the first marathon took place in 490 BC, after the Battle of Marathon between the Greeks and the Persians.

As the story goes, a Greek soldier named Pheidippides ran from the battlefield of Marathon to Athens, a distance of about 25 miles (40 km), to deliver the news of the Greek victory. According to the historian Herodotus, Pheidippides arrived in Athens, delivered the news, and then collapsed and died from exhaustion.

Incidentally however, according to Google Maps, the walking (or running) distance between these cities is around 34-35 km depending on the route taken.

So where did the marathon distance come from?

The answer can be traced back to the 1908 Olympic Games held in London, England. At that time, there was no standardised distance, and the race organisers had the freedom to choose a distance they thought was suitable.

According to the story, the marathon in the 1908 Olympic Games was supposed to be a distance of 25 miles (40.2 km) which was the distance of the marathon in the previous Olympic Games. However, the race started at Windsor Castle and ended at White City Stadium, which was about 26 miles away. To make the race finish in front of the royal family’s viewing box, an additional 385 yards (352 meters) was added, bringing the total distance to 26.2 miles.

The distance of 26.2 miles was officially recognized as the standard distance for a marathon by the International Association of Athletics Federations (IAAF) in 1921. The exact distance of 42.195 kilometers was established by the IAAF in 1924, and it has been the official distance of the marathon ever since!