The old port of Rorschach, lying at the foot of the Rorschacher Berg in a wide bay, the most southerly in Lake Constance (Obersee), was once an important trading post for the town of St Gallen. Its principal industries are textiles, metalworking and piano manufacture ("Sabel"). The pumping station for
the supply of Lake Constance water to St Gallen is here.
The development of Rorschach was closely bound up with economic prosperity of the abbey of St Gallen. As early as A.D. 947 it was granted the right to hold markets, coin money and levy tolls by the Abbot of St Gallen. The old dock was enlarged in 1484, enabling the town to carry on a considerable trade, particularly in corn. In the 18th C. the linen trade also flourished. In 1803, on the dissolution of the abbey, Rorschach passed to the canton of St Gallen.