The TT Circuit Assen is a motorsport race track built in 1955 and located in Assen, Netherlands. Host of the Dutch TT race, it is considered "The Cathedral" of motorcycling by the fans. It has a capacity of 100,000 spectators, including 60,000 seats. Since 1992 it is also part of the Superbike World Championship calendar.The original Assen track was first used for the 1925 Dutch TT (Tourist Trophy) race, held on country roads through the villages of Borger, Schoonloo and Grolloo, and organized by the Motorclub Assen en Omstreken. The brick-paved track had a length of 17.75 miles (28.57 km). The winner was Piet van Wijngaarden on a 500 cc Norton with an average speed of 91.4 kilometers per hour (56.8 mph). In years afterwards the Dutch TT was held on a road circuit through de Haar, Barteldbocht (near Assen), Oude Tol, Hooghalen, Laaghalen and Laaghalerveen. In 1951 the Italian Umberto Masetti took the record on a 500 cc Gilera with an average speed of 100.88 miles per hour (162.35 km/h). In 1954, Geoff Duke of Great Britain reached 106.06 miles per hour (170.69 km/h). The circuit remained unchanged until 1955, when a whole new circuit was built close to the site of the original, but less than a third of the length and much more like a modern road racing circuit. The circuit was fundamentally redesigned again in 2006, becoming the so-called A-Style Assen TT Circuit. All alterations aside, only one section of the circuit is original; the finish line never moved.