The Great Stalacpipe Organ is identified in Trevor Cox’s The Sound Book as one of the sonic wonders of the world. It is nestled deep underground amongst the water-dripping stalactite’s of the Luray Caverns in Virginia. The Stalacpipe Organ’s acoustic resonance is created from rubber plungers that tap one of thirty seven individual stalactite formations, most of which have been filed to produce the scale of notes you hear.