Waisenhaus (also Amthaus I) is the last remaining building of the Oetenbach nunnery in Zurich, Switzerland, and today houses the city police department.

Built outside of the historical core of the medieval town of Zurich, previously the Celtic-Roman Turicum, the former Zucht- und Waisenhaus ("penitentiary and orphanage") is the last remaining structure of the Oetenbach nunnery at the Lindenhof-Silhlbühl hill on the western shore of the Limmat river.

In 1601 the building was extensively remodeled and equipped with stepped gables, and as police barracks, in 1872 the remains of wall paintings were discovered.

[1] When the remaining buildings of the Oetenbach nunnery were broken, the occasion was not used by the archaeologists to secure finds of the Oppidum Lindenhof.

[1] Gustav Gull integrated the Stadhaus building between 1911 and 1914 in the Urania complex, and the former cellar at the entrance floor of the Waisenhaus building was redesigned on behalf of Emil Klöti by Augusto Giacometti between 1923 and 1925 with vault and wall paintings, which are considered as a work of art of national importance.