The Rigi-Scheidegg Railway, built in 1874, used to be Europe's highest adhesion railway. The line went out of service in 1942 and the tracks were subsequently demolished. However, you can still hike along the railway's historic structures. The Society for the Art of Engineering has put together a hiking route from Rigi Kaltbad to Rigi Scheidegg.
A PDF file with the hiking route and background information on the enigneering structure can be downloaded here (only available in German).
