Gernsbach is a town in the district of Rastatt, in Baden-Württemberg, Germany. It is located on the river Murg, 7 km (4.35 mi) east of Baden-Baden in the Black Forest. Twin towns are Baccarat in France and Pergola, Marche in Italy. The town is the historic centre of the lower Murg Valley and forms a central place of mid-size with Gaggenau. It is located in the Region Mittlerer Oberrhein, one of the twelve spatial planning regions of Baden-Württemberg. Gernsbach is an officially recognised climatic spa with a historic centre. Furthermore, Gernsbach is noted for its paper industry and Paper Centre, a service provider in the field of training, staff qualification and management consultancy for the German and Swiss paper and pulp industry.

The Murg is an 80.2-kilometre-long river and tributary of the Rhine in Baden-Württemberg, Germany. It flows through the Northern Black Forest into the Upper Rhine Plain, crossing the counties of Freudenstadt and Rastatt.