For one beautiful day nearly 50 years ago, bicyclists had a freeway in San Diego all to themselves.

Before opening a new section of Interstate 805 to vehicle traffic, highway officials invited bicyclists for a Community Cycle Day along 7 miles of roadway on March 19, 1972. According to news accounts from the time, they expected a few hundred riders. More than 8,000 turned up.

Most enjoyed a pleasant afternoon, pausing for picnics and enjoying unhurried views of the mesas and canyons from a 100-foot bridge free of noise and billowing exhaust. But crashes mounted on a long downhill, where some riders were reported to surpass speeds of 50 miles an hour. At least four people were hospitalized, officials said.

Exasperated patrolmen with bullhorns put a stop to the ride four hours ahead of schedule, hustling everyone onto the next exits. An Associated Press story the next day ran under the headline “Bike mayhem ends freeway preopening.” Dan Hancock shared a few slides taken by his father, Robert Hancock. 👇

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