Prahova Valley (Romanian: Valea Prahovei) is the valley where the Prahova river makes its way between the Bucegi and the Baiu Mountains, in the Carpathian Mountains, Romania. It is a tourist region, situated about 100 km north of the capital city of Bucharest.
Geographically, the Prahova river separates the Eastern Carpathians chain from the Southern Carpathians. Historically, the corridor was the most important passage way between the principalities of Wallachia and Transylvania. The present DN1 road, linking Bucharest with the city of Braşov and the future A3 will be built along the Prahova Valley.