Which technique where the roller coaster is allowed to coast through the ride's circuit through the force of gravity is used in Adventure World since 1991?
Turbo Mountain:  When the ride was moved to "Adventure World" in 1991, the ride's lift hill was modified from a spiral lift hill to a standard chain lift hill due to maintenance. Lift hill: A lift hill, or chain hill, is an upward-sloping section of track on a roller coaster on which the roller coaster train is mechanically lifted to an elevated point or peak in the track.
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