Corkscrew is an Arrow Development prototype Corkscrew roller coaster located at Silverwood Theme Park. Ten exact replicas of this same design were produced 1975–1979 at other scattered parks, followed by numerous other installations around the world featuring updated supports. After being sold as the prototype, this corkscrew originally operated at Knott's Berry Farm from 1975–89. Developed by Ron Toomer of Arrow Dynamics, a Utah-based design firm, the "Corkscrew" was the first modern steel inverting roller coaster open to the public, with identical models opening at three other parks days later.