Bischwiller (French pronunciation: [biʃvilɛʁ] ⓘ; German: Bischweiler; Alsatian: Bíschwiller)[a] is a commune in the Bas-Rhin department in Grand Est in northeastern France,[4] just west of the river Moder.

The Moder, a Rhine tributary, flows across the town.

Among the other streams which cross the area can be cited the following tributaries of the Moder: the Rothbaechel, the Erlengraben and the Waschgraben.

The last one is formed by the confluence of two smaller streams named Weihergraben and Schnuchgraben.

Due to its large Turkish minority, Bischwiller has been pejoratively dubbed "Turcwiller" or "Bischtanbul".