These early coasters were made famous by LeMarcus Thompson and first opened at New York City’s Coney Island in 1884. Though Richard Knudson patented the design first, it was Thompson that brought them to the masses.
Riders would climb to the top of the structure and get in the car. It would then gently, at around 6 mph (10 km/h), undulate to the ground. There it would be pushed up the other side by workers. At the top, the car would be “switched” onto the parallel return track and sent back to the start.
Rendering of a computer re-created Switchback.