|Canton :||Graubünden (GR)|
|Political community :||Casti-Wergenstein|
|Postal code :||7433|
Wergenstein was an independent political municipality in the former district of Hinterrhein , Canton of Graubünden , Switzerland . In 1923 Wergenstein merged with the former municipality of Casti to form the new municipality of Casti-Wergenstein .