Poole’s Cavern

Caves generally form on water-filled passages below the water table, where limestone is saturated with water. Cave formation is thought to have been taking place at Poole's Cavern for at least two million years.
A slow drip of water will form a solid platelet crystal, slowly growing into a stalactite, hanging down from the cave roof like this pretty row of new stalagtite in Poole’s Cavern.