The Great St Bernard Pass is the third highest road pass in Switzerland, at an elevation of 2,469 m. It connects Martigny in the canton of Valais in Switzerland with Aosta in the region Aosta Valley in Italy. It is the lowest pass lying on the ridge between the two highest mountains of the Alps, Mont Blanc and Monte Rosa. It is located on the main watershed that separates the basin of the Rhône from that of the Po.