Vipava Valley is a valley in western Slovenia. It lies between Italy on the west and Nanos on the east, and between Trnovski gozd on the north and Karst plateau on the south. Main towns are Ajdovščina and Vipava. Vipava river flows through the valley.
It has mild Mediterranean climate and is suitable for farming of different fruits and wines. Valley is also strongly influenced by burja, which reaches its peak in winter months at speeds of over 200 kmph.
Vipava valley was first colonized in 8000 BC. In antique, it was under Roman reign. In 394 it was place of battle of Frigidus. In the Middle Ages the valley belonged to the Dutchy of Carniola. After the end of the World war I it became part of Italy until the end of the World war II, when it became part of Yugoslavia.