is visible on the west. Its boundaries are the
Aosta Valley on the south,
Ossola valley on the east and
Rhone valley on the north. It is separated from the
Mont Blanc Massif by the
Val Ferret, and the
Lepontine Alps by the
Simplon Pass. The black line demarks the
Swiss-Italian and
Swiss-French borders. The main chain (
watershed between the Mediterranean Sea and the Adriatic Sea) runs from west to east on the border between Italy (south) and Switzerland (north). From
Mont Vélan, the first high summit east of
St Bernard Pass, the chain rarely goes below 3000 metres and contains many
four-thousanders such as
Matterhorn or
Monte Rosa. The valleys are quite similar on both side of the border, being generally oriented perpendicular to the main chain and descending progressively into the
Rhône Valley on the north and the
Aosta Valley on the south. Unlike many other mountain ranges, the higher peaks are often located outside the main chain and found themselves between the northern valleys (
Grand Combin,
Weisshorn,
Mischabel,
Weissmies). ==Peaks==