Le Mans Grand Prix d'Endurance, also known as the Le Mans 24-Hour Race, remains the most prestigious of all endurance races. It has been held almost every year since 1923 at the 8.5-mile (13.7-kilometer) Sarthe road-racing circuit near Le Mans, France. Multiple classes of vehicle compete side-by-side, with prizes going to both the overall winner and the winner of each class.
Le Mans is the first jewel in endurance racing's Triple Crown, as the three most historically challenging endurance races are known. The 24 Hours of Daytona, held at Daytona International Speedway in Daytona Beach, Fla., and the 12 Hours of Sebring, held at Sebring International Raceway, a former Army Air Force base in Sebring, Fla., round out the Triple Crown.
The 24 Hours of Daytona has changed its name as it has gone through various sponsors (it's currently called the Rolex 24 at Daytona), but the race has remained much the same. Drivers pit touring cars and Daytona prototypes against one another on a 3.5-mile (5.6-kilometer) combined road course. Part of the race takes place on the NASCAR track, and part occurs on a winding infield road course. Daytona's tri-oval track has a shape between an oval and a triangle, and has consequently sharper turns than a squared oval or true oval track.
Run on one of the oldest continuously operating racetracks in the United States, the 12 Hours of Sebring race consist of a 3.7-mile (6-kilometer), 17-turn road course featuring long straight-aways, blistering high-speed turns and challenging slow corners. Race fans know the Sebring track for its rough and bumpy surface, parts of which run along old sections of World War II-era landing fields. These difficult conditions, combined with the heat of south central Florida, make Sebring a truly demanding course for both car and driver.
The popularity of endurance motorsport has given rise to several racing series, usually inspired or anchored by a major championship race. Prominent examples include the Rolex Sports Car Series of 12 races, which begins with the 24 Hours of Daytona, the American Le Mans Series (ALMS) and the Le Mans Series (LMS).
You might imagine that all of the engineering that goes into making reliable, fuel-efficient endurance racers could be put to good use in consumer cars. As we'll see in the next section, you're right on the money.