Put simply, limestone is a type of rock that is formed by organisms ... you typically are thinking of gravel — irregular ...

Limestone Pavements are bare limestone rock surfaces composed of slabs of rock (clints), separated by variable-width vertical cracks (grikes) . These grikes have developed by weathering and ...

Vietnam's Son Doong cave is so large, you could squeeze 15 Great Pyramids of Giza inside it and fly a Boeing 747 airplane through some of its passages.