Ansitz Thurn, Cultural heritage monument in Bolzano, Italy

Ansitz Thurn is a late-13th-century residential tower at Dr.-Streiter-Gasse 27–27a in Bolzano, with a 10 × 9 m footprint, cellar, ground floor and three upper storeys. Its late-Gothic form, added around 1500, has stepped gables, corner oriels and squared-off plaster framing, plus a north wing linked by an arch over the lane. Inside are two late-Gothic halls, the Petersaal with a wooden coffered ceiling and a 14th-century Gothic biforium window fragment.

Ansitz Thurn was first mentioned at the end of the 13th century as the seat of the von Thurn (de Turri) family; the original residential tower measured 10 by 9 metres. After the family died out in 1461, the building passed to the von Niedertor family, and in 1497 it became the property of Bartholomäus von Firmian. From 1571 it belonged to the Khuen von Belasy barons, and in 1637 it passed to the Zallinger merchant family from Füssen, which took the predicate zum Thurn.

The name Thurn derives from the family von Thurn (de Turri), first recorded here at the end of the 13th century. In the Petersaal, a 15th-century alliance coat of arms of the noble families Firmian and Tänzl von Tratzberg is visible. Since 1637 the house has belonged to the Zallinger merchant family from Füssen, which took the predicate "zum Thurn".

The tower at Dr.-Streiter-Gasse 27–27a stands between the Lauben arcades and Dr.-Streiter-Gasse, and the arch spanning that lane links it to the Ölhaus at number 20. Both the tower with the adjoining house Lauben 32 and the arch with the Ölhaus are listed monuments, so the exterior is what visitors come to see; the halls are not open as a regular attraction.

The tower at Dr.-Streiter-Gasse 27–27a has been listed with the neighbouring house Lauben 32 since 1950; the arch over the lane was added to the register in 1977 together with the Ölhaus at Dr.-Streiter-Gasse 20. The building passed by inheritance: after the Thurn family died out in 1461 it went to the Niedertor, in 1497 to Bartholomäus von Firmian, from 1571 to the Khuen von Belasy and in 1637 to the Zallinger family from Füssen, who took the title "zum Thurn".