What geographical feature is characterized by a deep valley between mountain ranges?

A gorge is defined as a narrow and deep valley between cliffs or steep slopes, typically formed through the erosion by a river or other geological processes. This makes it distinct from other geological features. While both canyons and gorges are related, a canyon tends to be wider with more gradual slopes, making gorges narrower and deeper by comparison. A plain is a flat or gently rolling area of land with little elevation change, and a plateau is an elevated flat area that often has steep sides. Therefore, the characteristics of a gorge being a deep valley between mountain ranges specifically highlight its formation and shape, making it the correct answer in this context.