Threatened Rock Shelters in Islamabad

A ‘rock shelter’ (also known as rock house, crepuscular cave or ‘abri’) is a shallow cave-like opening at the base of a bluff or cliff. ‘Rock shelters’ form because a rock stratum such as sandstone, which is resistant to erosion and weathering, has formed a cliff or bluff, but a softer stratum, more subject to erosion and weathering, lies just below the resistant stratum, and thus undercuts the cliff.