The Wengernalp Railway (German: Wengernalpbahn, WAB) is a 19.11 kilometres (11.87 mi) long rack railway line in Switzerland. It runs from Lauterbrunnen to Grindelwald via Wengen and Kleine Scheidegg, making it the world's longest continuous rack and pinion railway.[1] The name refers to the alpine meadow of Wengernalp, above Wengen.

The line is normally operated in two sections, with trains from either direction terminating at Kleine Scheidegg. At the latter station, most passengers transfer to the Jungfrau Railway for the continuation of the journey to the highest railway station in Europe at Jungfraujoch. There are generally no roads to Wengen/Mürren, and the train is the main access.

The line is owned by the Wengernalpbahn AG, a subsidiary of the Jungfraubahn Holding AG, a holding company that also owns the Jungfraubahn and Bergbahn Lauterbrunnen–Mürren, Harderbahn, and Firstbahn. Through that holding company it is part of the Allianz - Jungfrau Top of Europe marketing alliance, which also includes the separately owned Berner Oberland-Bahn and Schynige Platte-Bahn