The Uetliberg railway line (German: Uetlibergbahn) is a passenger railway line which runs from the central station in the Swiss city of Zürich (Zürich HB SZU) through the city's western outskirts to the summit of the Uetliberg.

The route serves as line S10 of the Zürich S-Bahn, with the Zürcher Verkehrsverbund's (ZVV's) standards zonal fares applying.

The original electric rolling stock had many of the attributes of contemporary tramcars, and were designed to be regaugeable to metre gauge as there was a (never realised) plan to integrate the line with the Zürich tram network.

This extension involved the construction of a new rail tunnel from Selnau to Zurich HB, and a new underground intermediate station adjacent to the former terminus.

The underground platform and tracks used at Zurich HB were already in existence, having been built prior to 1973 for a U-Bahn scheme that was ultimately rejected by voters.

However an increase in train frequencies in that year meant that the possibilities of running the stock was much reduced, and depot capacity was at a premium.

The train, made up of motor car 2 and trailer C41, has since been loaned to the Swiss Transport Museum in Lucerne.

On Saturdays, Sundays and public holidays, trains run the full length of the line every 20 minutes.

Until about 2014 most of the trains were operated by three car sets, with two Be 4/4 motor coaches from the series 521–528 sandwiching a low floor intermediate trailer.

The two older Be 8/8 cars 31 and 32, with no low floor access, were used for short workings, reversing at Triemli station.