In a second contract in the summer of 1896, Siemens agreed with Charlottenburg and Schöneberg to an extension of this route from Bülowstraße to the Zoological Garden.

It was intended that at the former Auguste-Viktoria-Platz, today's Breitscheidplatz, an elevated railway system with a house passage should be created in order to not take the shine of the new building of the Kaiser Wilhelm Memorial Church.

The station, originally designed by Alfred Grenander, opened on 14 December 1902 as the western terminus of the first U-Bahn line (Stammstrecke) to Warschauer Brücke.

It was named Knie ("knee") after a curve there on the historic road between the cities of Berlin and Charlottenburg, the present-day Straße des 17.

In 1953, the station and the eponymous square, a large roundabout, were renamed after the West Berlin mayor Ernst Reuter and extensively remodeled until 1959.