The world’s strangest musical instrument is located in one of the most unlikely places in the world — deep underground, inside Virginia's Luray Caverns, in the United States. Sitting atop a pedestal, surrounded by hundreds of hanging stalactites, it appears to be a normal organ. But instead of using metal pipes, the Great Stalacpipe Organ uses the entire cave itself to produce music. Electronically wired to each key of the organ’s keyboard are rubber-tipped mallets that softly strike against the ancient stalactites of various lengths and thickness to produce a distinct tone that sounds very much like a xylophone. The organ is connected to exactly 37 different stalactites scattered over 3.5 acres of the caverns, which makes the Great Stalacpipe Organ, in one way, the worlds largest musical instrument.

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