The Nagelfluhkette is a mountain range located in Bavaria, Germany and Vorarlberg, Austria, bordering on the northern edge of the Allgäu Alps. It has a maximum altitude of 1,834 m above sea level. Its name derives from the rock type Nagelfluh. In older and geological literature, as well as in the local vernacular language, one also finds the term Hochgratkette.

The Bregenzerwald is one of the main regions in the state of Vorarlberg (Austria). It overlaps, but is not coterminous with, the Bregenz Forest Mountains, which belong to a range of the Northern Limestone Alps, specifically the northern flysch zone. It is the drainage basin of the Bregenzer Ach river.