Summer rodelbahn

A Sommerrodelbahn is a form of dry toboggan run. Located on the side of a steep hill, it may consist of a track or rail upon which cars or carriages run downhill at high speed or simply a concave concrete trough down which participants slide on plastic 'toboggans'.

An example of a Sommerrodelbahn may be seen in the Austrian village of Pettneu. It is 550 metres (601 yards) in length.

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Wikipedia