This is the "Wuppertal Schwebebahn", a suspension railway in Wuppertal, Gemany, filmed in 1902. It's "the oldest electric elevated railway with hanging cars in the world," and... it's still in service!
Designed by Eugen Langen and offered first to the cities of Berlin, Munich and Breslau who all turned it down, the installation with elevated stations was built in Barmen, Elberfeld and Vohwinkel between 1897 and 1903; the first track opened in 1901. The railway line is credited with growth of the original cities and their eventual merger into Wuppertal. The Schwebebahn is still in use as a normal means of local public transport, moving 25 million passengers annually, per the 2008 annual report. New rail cars were ordered in 2015, called Generation 15, and the first new car went into service in December 2016.
The Schwebebahn runs along a route of 13.3 kilometres (8.3 mi), at a height of about 12 metres (39 ft) above the River Wupper between Oberbarmen and Sonnborner Straße (10 kilometres or 6.2 miles) and about 8 metres (26 ft) above the valley road between Sonnborner Straße and Vohwinkel (3.3 kilometres or 2.1 miles)...
Enjoy a ride on "The Flying Train"!