盖瓦什是土耳其的城镇，由凡城省负责管辖，位于该国东南部凡湖南岸，距离首府凡城40公里，面积727平方公里，海拔高度1,750米，2011年人口10,366。

Gevaş (Armenian:Ոստան, Vostan, meaning "[princely] court"; Kurdish:Westan‎) is a district of Van Province of Turkey. The mayor is Sinan Hakan (AKP). It is located on the south shore of Lake Van.

Historically, Gevaş was for some time the main town of the Armenian kingdom of Vaspurakan and later between the 14th and 15th centuries the centre of a small Kurdish emirate. In their time the settlement had moved nearer to the lake. Later the town was incorporated in the Ottoman Empire. Before World War I the district had a Muslim majority with a large Christian Armenian minority.