Wasserturm des Dortmunder Südbahnhofs, Water tower and architectural monument near Südbahnhof, Dortmund, Germany.

The Wasserturm des Dortmunder Südbahnhofs is a 52-metre-high building whose upper third holds two reinforced-concrete tanks of 800 m³ each. Behind the brick facade is a reinforced-concrete skeleton frame, and the surrounding cornices divide the building without carrying any load. The ground floor originally held shops, while the upper floors contained a bathing establishment and overnight rooms for train crews and workshop staff.

The Deutsche Reichsbahn built the tower between 1925 and 1926 as part of the Dortmund Süd railway depot, and it supplied boiler feed water to steam locomotives until the 1950s. After that role ended, the building was converted to offices, now housing the office of architect Ralf Schulte-Ladbeck and several agencies.

The social spaces within reflect how the railway cared for its workers in the early 20th century. Changing rooms, washing facilities, and staff quarters show the company's commitment to employee welfare.

Today the building functions as offices and can be viewed from the outside, with its red brick structure clearly visible from the railway yard area. Visitors can explore the surroundings at any time, as the forecourt of South station provides good access.

The two 800 m³ reinforced-concrete tanks occupied the upper third of the 52-metre building, and the surrounding cornices that band the brick facade carry no structural load at all. The ground floor originally held shops, while upper floors had a bathing establishment and overnight rooms for train crews and workshop staff.