A wooden roller coaster is most often classified as a roller coaster with laminated steel running rails overlaid upon a wooden track. Occasionally, the structure may be made out of a steel lattice or truss, but the ride remains classified as a wooden roller coaster due to the track design. Due to the limits of wood, wooden roller coasters in general do not have inversions (when the coaster goes upside down), steep drops, or extremely banked turns (overbanked turns). However, there are exceptions; Son of Beast at Kings Island has a 214-foot-high (65 m) drop and originally had a 90-foot-tall (27 m) loop until the end of the 2006 season, although the loop had metal supports. Other special cases are Hades at Mount Olympus Water and Theme Park in Wisconsin Dells, Wisconsin, featuring a double-track tunnel and a 90-degree banked turn, The Voyage at Holiday World (an example of a wooden roller coaster with a steel structure for supports) featuring three separate 90-degree banked turns, Ravine Flyer II at Waldameer Park which has a 90-degree banked turn, and T Express at Everland in South Korea with a 77-degree drop.