Schloss Blatten, Medieval castle ruins in Oberriet, Switzerland.

Schloss Blatten is a medieval castle ruin situated on a rocky elevation near the Rhine River. The square tower with its preserved fortification walls and gate structure form the main features of this site.

The castle was built before 1270 by the Abbot of St. Gallen, Berchtold von Falkenstein, as a defensive fortress against the Counts of Montfort-Werdenberg. Ownership changed hands multiple times until 1799, when it was destroyed during the French War.

The castle reflects regional building traditions of St. Gallen and remains an important cultural landmark for the area. Visitors can observe how such structures were integrated into the surrounding landscape and settlement patterns.

Visitors can access the ruins on the elevated ground with views over the Rhine valley. From April to September, a seasonal restaurant operates in a wooden building above the preserved vaulted cellar.

Locals call the ruin Schloss Blatten rather than Burg Blatten. Since April to September the Oberriet ski club runs a Schlosswirtschaft, a seasonal inn, in a wooden building erected on the surviving vaulted cellar; the tower interior has no floors left.