After the water had been mostly removed by a lowering in the water table, these eroded forms remained and growth began to take hold via stalactites, stalagmites, columns, etc. Some notable formations include the Leaning Column, undermined and tilting like the campanile of Pisa; The Great Stalacpipe Organ, a large shield formation, that was used from very early on as an instrument for a variety of folk and religious songs; and a vast bed of disintegrated carbonates left by the water in its retreat through the great space called the Elfin Ramble.