Longest rideable miniature hobby railway

Train Mountain Railroad Museum near Chiloquin, Oregon, USA, has a total of 35,847 m (117,610 ft) of 19 cm (7½ in) gauge track, with 20,533 m (67,366 ft) of 'mainline' track, and the remainder comprising yards and sidings. 7½ in gauge trains (they are not generally known as 19 cm gauge) are large enough to carry passengers (in single file) but small enough for enthusiasts to transport them in the back of pickup trucks or on trailers, and this is therefore the most popular gauge for such railways. Train Mountain is a non-profit organisation which holds regular meets where its members get together and drive their trains. http://www.trainmountain.org