Wikipedia
Sommerrodelbahn
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 in length.