Reason why the marathon is exactly 26.2 miles instead of a round number

The London marathon took place on Sunday, with Ethiopia's Tigst Assefa surging to victory in the women’s race, Kenya's Sebastian Sawe triumphing in the men's only field, and thousands of amateurs hitting the tarmac in pursuit of personal records.

This year’s race had us thinking: Why is a marathon exactly 26.2 miles?

Well, the concept of a marathon originated from the story of Pheidippides, a soldier who in 590 BC is said to have run from Athens to Sparta to request help when the Persians landed at Marathon, Greece.

It is claimed that he ran about 240 km in two days before returning.

Pheidippides is then thought to have run 40 kilometres (24.8 miles) from Marathon to Athens to deliver news of victory in the Battle of Marathon over Persia.

Pheidippides is said to have said the words, “we win” upon arriving in Athens, before collapsing and dying.

While that story is often tied to the marathon distance, the modern 26.2 mile standard originates from the 1908 London Olympic Games.

The organisers decided that the marathon distance that year would be 26.2 miles, as they wanted to start the race at Windsor Castle, and gave the finish line in front of the royal box at the Olympic stadium.

Pheidippides arrived in Athens with news of the Greek victory over the Persians at Marathon, only to die on the spot (Getty)

The route, which featured an extra 385 yards than previous races, resulted in the distance of 26 miles and 385 yards. This became the standard distance after the 1908 Games.

Indeed, in 1921 the International Amateur Athletic Federation formally adopted the distance.

In turn, the 56,000 amateur runners taking on the race around the capital on Sunday, raced a 26.2 mile course.

Many will be running the 45th annual London Marathon hoping to raise funds for charities and good causes.