How it works
The 1908 London Olympic course ran from Windsor Castle to the stadium with a finish positioned before the royal box, producing the distance later adopted as the standard.
What people often miss
The modern race is inspired by the ancient story of a messenger running from Marathon, but the exact 42.195-kilometer distance is a twentieth-century sporting standard.
Why this question comes up
The oddly specific distance is a common question during major city marathons.
Key points
- The official marathon distance is 42.195 kilometers, about 26.2 miles. It was standardized after early Olympic marathons varied in length.
- The 1908 London Olympic course ran from Windsor Castle to the stadium with a finish positioned before the royal box, producing the distance later adopted as the standard.
- The modern race is inspired by the ancient story of a messenger running from Marathon, but the exact 42.195-kilometer distance is a twentieth-century sporting standard.
Bottom line
The official marathon distance is 42.195 kilometers, about 26.2 miles. It was standardized after early Olympic marathons varied in length.
Source and verification
This Answer was checked against World Athletics: Marathon. Follow the source for the full official explanation and any later updates.