Track grip (adhesion) on the Hauenstein line caused him concern. The difficulties led Riggenbach to the concept of the rack railway. After many attempts he discovered that one could negotiate steeper stretches of track by bolting a rack between the rails, which a toothed wheel or cog on the underside of the locomotive could engage. He built his first locomotive in 1862, and on 12 August 1863 France awarded him Patent No. 59625 for the invention. The Vitznau-Rigi line was inaugurated in 1871 as the first mountain railway to use the Riggenbach system in Europe. The locomotives were equipped with his counter-pressure braking system.