The Wengernalp Railway is an 800 mm gauge rack and pinion railway (Riggenbach-Pauli system) and is the longest cog - wheel railway in Switzerland.

It runs from Lauterbrunnen to the head of the Kleine Scheidegg pass where it connects to the Jungfrau Railway.

The line was opened in 1893 and electrified in 1909/10 using 1500 V direct current.