What happens if I leave the marked course?

• You may leave the marked course with the permission and under the supervision of an official, as long as going off course does not shorten the distance you cover.
• If the Referee is satisfied, on a report from a Judge or Umpire or otherwise, that you left the marked course and so shortened the distance, you are disqualified.
• The rules say umpires should be placed at regular intervals and at each key point, with others moving along the course during the race.
• The course must be on made-up roads, though a marked bicycle path or footpath alongside the road may be used when traffic makes the road unsuitable (not soft ground such as grass verges). The course length cannot be less than the official event distance, and the distance in kilometres on the route must be displayed to all athletes.

Source: World Athletics Technical Rules (Book C, C2.1), Part VII Road Races, in the edition updated 1 July 2026: https://worldathletics.org/about-iaaf/documents/book-of-rules