Heinrich-Sauermann-Haus, Cultural heritage monument in Flensburg, Germany

The Heinrich-Sauermann-Haus is a castle-like museum building erected 1900–1903 above Rathausstraße on the eastern edge of Christiansen Park. Architect Carl Mühlke designed it in Northern Renaissance style, drawing on an 1891 plan by Schulz & Schlichting; it resembles Frederiksborg Castle. Its facade carries the Flensburg coat of arms above the main entrance, a sundial on the south side, a Nordic dragon head and a German imperial eagle on the west side.

The building was constructed between 1900 and 1903 based on architect Carl Mühlke's designs to serve as a municipal museum. Its creation coincided with the city's decision to establish a dedicated home for its growing collections.

The building displays regional artworks and furnishings that reflect the tastes and craft traditions of northern German society across different periods. The collections throughout the rooms give you a sense of how people in this region lived and decorated their spaces over time.

The building stands above Rathausstraße at the eastern edge of Christiansenpark, next to the Hans-Christiansen-Haus, at Museumsberg 1. A stairway from Rathausstraße leads up to the museum; its construction began in 1905. The natural history museum occupies the ground floor, while the arts and crafts collection is shown upstairs.

The facade carries several details attributed to Heinrich Sauermann's involvement: the Flensburg coat of arms above the main entrance, a sundial on the south side, a Nordic dragon head, and a German imperial eagle on the west side. The rear central entrance bears the inscription "Arbeit staelt – Kunst beseelt".