On 21 June 2001, 20-year-old Gemma Savage died following an accident the previous day when two carriages collided on Treetop Twister, a spinning Wild Mouse roller coaster, which had opened in May of that year. Police decided not to prosecute a maintenance worker, who claimed that he had only received an hour of training on that ride and had not seen its manual. Faulty wiring had also caused a malfunction on the ride. In October 2004, Deputy Coroner John Sleightholme at Skipton Magistrates' Court ruled death by misadventure.