On the north is the valley of Chamonix, and on the east the head of the valley of Aosta.
This great valley—one of the most considerable on the southern side of the Alps—has attracted special attention, in ancient as well as modern times, from its leading to two of the most frequented passes across the great mountain chain—the Great and the Little St Bernard—the former diverging at Aosta, and crossing the main ridges to the north into the valley of the Rhone, the other following a more westerly direction into Savoy.
Below Aosta also the Dora Baltea receives several considerable tributaries, which descend from the glaciers between Mont Blanc and Monte Rosa.
The kings uncle is duke of Aosta, his son is prince of Piedmont and his cousin is duke of Genoa.
Farther west came the roads over the higher Alpine passes the Brenner from Verona, the Septimer and the Splugen from Clavenna (Chiavenna), the Great and the Little St Bernard from Augusta Praetoria (Aosta), and the Mont Genvre from Augusta Taurinorum (Turin).