San Bernardino County history: Ontario Motor Speedway

"San Bernardino County Update", yellow arrowhead and "SBCounty.gov

A black and white image shows a crowded racetrack with multiple cars speeding around the track. — *Ontario Motor Speedway.*

Ontario Motor Speedway, also known as the “Big O,” was a motorsports venue located in Ontario. It was the first and only automobile racing facility designed to accommodate major races sanctioned by four major racing organizations including NASCAR, the United States Auto Club, the National Hot Rod Association and Formula One.

The $25.5 million track, modeled after Indianapolis Motor Speedway, opened in August 1970 and was considered state of the art at the time. The facility featured a 2.5-mile oval track, a 3.2-mile infield road course and a quarter mile drag strip to accommodate a variety of racing events.

The Speedway’s “Big O” electronic sign could be seen from the then incomplete Interstate 10 and Interstate 15 interchange. The inaugural California 500 Indy car race took place on Sept. 6, 1970, drawing more than 170,000 attendees. Jim McElreath won the race after passing Art Pollard on the final lap. California Gov. Ronald Reagan presented the winner’s trophy.

Beyond auto racing, the Speedway hosted a variety of events and concerts. In 1971, Ontario Motor Speedway staged motorcycle daredevil Evel Knievel’s record jump over 19 cars before a crowd of 50,000. In 1974, the Speedway hosted California Jam, a rock festival that drew an estimated 300,000 to 400,000 and was considered the largest paid attendance for a rock concert at the time. Portions of the concert were televised nationally.

Amid financial struggle, the Ontario Motor Speedway was purchased for real estate development. The facility was demolished in 1981 at a cost of $3 million.

Subsequent development, including offices, housing, retail stores and the Citizens Business Bank Arena, has largely covered the old racetrack grounds. Although virtually nothing remains of the racetrack, the city of Ontario has retained some of its history and heritage by building Ontario Motor Speedway Park a few blocks west of the racetrack site. Echoes of the Ontario Motor Speedway can also be found in racing inspired street names around the old racetrack such as Concours Street, Corvette Drive, Porsche Way, Mercedes Lane and Ferrari Lane.

Additional County Update News – August 20, 2026