Built near Los Angeles in 1970 at a reported cost of $25.5 million, it is ironic that Ontario Motor Speedway should close due to lack of funding. Originally given council approval in March 1966, the project was delayed when its original backers, a Culver City film production company, withdrew. The inaugural event on September 6 1970 was the Formula 1 versus F5000 Questor Grand Prix, won by Mario Andretti’s Ferrari on the road course. A full F1 World Championship race was scheduled in 1972 but was subsequently cancelled. After that, racing at Ontario was concentrated on the Superspeedway, whose nine degree turns made it quicker than Indianapolis. The California 500 was part of the USAC National Championship and subsequent Champ Car World Series for the decade Ontario remained in operation, and a capacity crowd of 180,000 watched the first full 500-mile IndyCar race held outside Indiana. It was acquired by the Chevron Land and Development Company and officially closed on December 16 1980.
