2003 1000 km of Le Mans

The 2003 1000 km of Le Mans was a one-off sports car event run under the organization of the Automobile Club de l'Ouest (ACO) in preparation for the Le Mans Endurance Series that began in 2004.

Previously, the FIA Sportscar and FIA GT Championships had run primarily in Europe, but were not running as a combined series, one concentrating on prototypes and the other grand tourers, and featured mostly sprint or middle-distance races.

In order to help bolster the number of entrants, the ACO promised winners in each of the four race classes automatic invitations to the 2004 24 Hours of Le Mans.

With this, the ACO pushed forward with their development of the Le Mans Endurance Series, debuting in 2004.

This move would also lead to the demise of the FIA Sportscar Championship, as prototype teams chose instead to participate in LMES.