What are the Aquitaine and Languedoc depressions north of the Pyrenees?

The Aquitaine and Languedoc are broad depressions located to the north of the Pyrenees mountain range. These regions serve as significant geographical features flanking the northern side of the mountains, receiving water from major rivers that flow out of the range, such as the Garonne River.1

The Aquitaine Basin, situated in southwestern France, is bounded by the Pyrenees to the south and the Massif Central to the northeast. Its landscape is characterized by limestone and marl plateaus in the north, while its southern low plateaus were formed by deposits of sand and gravel—known as molasse—that were stripped from the rising Pyrenees. The Languedoc depression similarly functions as a major lowland area bordering the northern extent of the mountain chain.21