Waaghaus, Historical weighing house in St. Gallen, Switzerland

The Waaghaus is a two-storey building at the eastern end of the Marktplatz, built in 1584–1585. Its ground floor is open on all sides, with large entrance gates once used by wagons, a paved floor rising slightly to the east, and stepped gables on the east and west facades. The west facade carries two rows of windows, a large clock with a moon-phase indicator and a roof turret with an onion dome, both taken from the old town hall demolished in 1877.

A council resolution of 1581 called for a house for weighing merchants' goods near the Brühltor, with two grain bins above; the building was erected in 1584–1585. It served weighing, customs and storage until the 19th century, when the railway station and new duty-free warehouses made it redundant. It briefly held a police post, then a post office from 1876 until the 1958 conversion.

The name refers to its past role as a weighing station, reflecting how important fair commerce was to the community. Its position on the market square today reminds visitors of the economic life that once centered on local trade and crafts.

The Waaghaus stands at the eastern end of the Marktplatz, where the exit toward the Brühltor and Rorschacherstrasse narrows; that passage is reserved for public transport and local access traffic. The ground floor is open around the perimeter and paved, rising slightly toward the east. The east side openings are recent, since that wall once belonged to the city fortifications.

The clock with a moon-phase display and the roof turret with its onion dome on the west facade come from the old town hall, demolished in 1877. Two large central windows once held a hoisting crane that lifted heavy linen bales into the upper floor for storage.