The Valle Po (Po valley) is a valley of the Cottian Alps in the province of Cuneo, Piedmont, northern Italy. It gives rise to the longest river in Italy, the Po, before it enters the Pianura Padana (or Plain of the Po). It has a length of some 32 km, from Saluzzo to Crissolo, and is home to the Monviso mountain. It is bounded by the Val Pellice, Valle Varaita and the Valle del Guil. The head of the valley is located at the Traversette pass (Colle delle Traversette) (2950 m above sea level). The valley descends through the King's plain (Pian del Re) (2020 m), where the Po river has its source.