The 1923 24 Hours of Le Mans, officially the 24 Hours Grand Prix of Endurance (), was the inaugural Grand Prix of Endurance, and took place on 26 and 27 May 1923. A strong field of twenty manufacturers entered, all from France aside from a single Bentley from Great Britain and a pair of Excelsiors from Belgium. In a rain-soaked race it was the Chenard-Walcker team and the Bentley that set the pace, chased by the smaller 2-litre Bignan. The Bentley was delayed by stones smashing a headlight and puncturing the fuel tank, and in the end the Chenard-Walckers of René Léonard / André Lagache and Christian Dauvergne / Raoul Bachmann had a comfortable 1–2 victory. However, there was no official victory for them as this event was the first part of three consecutive annual races, for the Rudge-Whitworth Triennial Cup, where the ultimate winner would be the manufacturer whose best car exceeded their nominated target distance by the greatest margin. So it was the small 1.1-litre Salmson of Desvaux/Casse that took the lead in that competition. It had completed 98 laps, 46 over its 52-lap target. The race was also an excellent exhibition of machine endurance and reliability. Thirty cars finished the event, a number not equalled at Le Mans again until 1993. Regulations The final regulations for the event were not completed by Charles Faroux and the Automobile Club de l'Ouest (ACO) until February 1923. All cars had to be standard 4-seater production models, except those under 1100cc which could be 2-seaters where at least thirty cars had been built. The vehicle had to carry 60kg lead ballast for each passenger space aside from the driver. A maximum of two drivers were allowed (but not riding together), and they alone could replenish the fluids (petrol, oil and water), although there was no minimum distance between refills as in later years. The fuel was to be supplied by the ACO. Engines had to be turned off at pit-stops, and only re-started with an onboard starter. All cars had to have standard touring equipment, such as wheel wings, hood (if a convertible), running boards, headlights, a rear-view mirror and ‘warning devices’ (horn). None of the entered cars had window-wipers. There was an hors course rule such that every car had to meet a certain ratio of their minimum distance at the 6, 12, and 18-hour marks or face disqualification. The