(slow music)

- To play the instrument that is utilizing our gentle Earth,

it's like you're becoming one with the instrument

in a very true way.

You just sit and go, yes.

We're looking at The Great Stalacpipe Organ

of the Luray Caverns in Luray, Virginia.

When I press a key, it sends an electrical pulse

up to a rubber-tipped mallet, which strikes the stalactite,

causing it to vibrate, and producing a incredibly beautiful

musical tone.

The area that the strikers cover is roughly

three and a half acres, which then makes it literally

the world's largest musical instrument.

(water dripping)

It is a very gentle sound, very peaceful.

There's only one like it in the world,

and it's something incredibly different

and wonderfully beautiful.

(water dripping)