The Landquart is a river of Switzerland in the canton of Grisons and a right tributary of the Alpine Rhine, formed by the confluence of two mountain streams, Vereinabach and Verstanclabach, that originate from glaciers in the Silvretta Alps. It flows northwesterly through the village of Klosters, the largest and uppermost village in the Prättigau valley, and empties into the Alpine Rhine near the town of Landquart. It is 38 km (24 mi) long, with a 615.17 km² (237.52 sq mi) drainage basin.