San Bernardino Pass (Italian:
Passo del San Bernardino, German:
Bernhardinpass, 2,066 metres (6,778 ft)) is a high mountain pass in the
Swiss Alps 
connecting the Hinterrhein and the Mesolcina (Misox) valleys between
Thusis 
(canton of Graubünden) and
Bellinzona 
(canton of Ticino). Located in the far eastern side of the Western Alps it is not to be confused with the
Great St Bernard Pass 
and the
Little St Bernard Pass 
. The top of the pass represents both the Italo-German language frontier and the watershed (drainage divide) between the Po basin and the Rhine basin. Marscholsee is within the pass at an elevation of 2,053 m (6,736 ft).
The route first became important as a mule track in the fifteenth century when the route between Thusis and
Splügen 
was known as the Via Mala. A road for wheeled vehicles was opened in 1770; this road was significantly improved between 1821 and 1823, financed in part by the Kingdom of Sardinia, keen to improve a trade route connecting Genoa and
Piedmont 
to the Graubünden that was not directly controlled by Austria.