U7 (Berlin U-Bahn)

The U7 is a rail line on the Berlin U-Bahn. It runs completely underground for a length of 31.8 kilometres (19.8 mi) through 40 stations and connects Spandau, via Neukölln, to Gropiusstadt and Rudow. The U7 was originally the south-eastern branch of the Nord-Süd-Bahn (U6) that ran between the branching point at Belle-Alliance-Straße (Mehringdamm) and Grenzallee; however, in the 1960s, this stretch was separated from the rest of the line and extended at each end to form a new line.

The U7 is Berlin's longest underground line, both in terms of absolute length and total travel time, and one of the longest all-subterranean lines in Europe.