According to a news release from the Wissahickon Valley Riders and Drivers Association, Forbidden Drive received its name after equestrians and spectators protested a proposal to open Fairmount Park trails to automobiles.

"A 'Save the Wissahickon' campaign rallied hundreds of equestrians and thousands of spectators. Forbidden Drive got its name from the proposal’s defeat, hence cars are 'forbidden,'" the release said.

Click here for more information on this year's Wissahickon Day Parade.