Hearing the bone-chilling sound of a wolf howling can be an unnerving experience, even more so if it is an entire pack.

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A visitor at the Wolf Creek Habitat in Brookville, Ind., captured this symphony of wolves.

Visitors to the Wolf Creek Habitat in Brookville, Indiana, recorded a video of about 30 animals harmonizing, joining their voices in a single heart-chilling howl.The lupine recital begins with a single soft ah-oooo, but not before long, more and more animals join in, turning a solo into a chorus of haunting notes.The wolves, held in separate enclosure areas, seem to call out to one another by emitting piercing, primal wails. In one of the pens, a quintet of white and grey animals jump onto a wooden platform as if they are singers ascending the stage.In the video, the wolves are captured raising their heads in unison to the sky and yowling ever louder, reaching a deafening crescendo both terrifying and beautiful.As soon as the lupine symphony appears to come to a conclusion, one of the animals would pick up again, with the others falling in with the chorus.YouTube user thesadistnationx uploaded the 1 minute 34 second footage on Monday after returning from a weekend trip to the wolf sanctuary that allow visitors to interact with the animals.'It was insane, and we were in one of the pack's cages right in the middle of it all,' the used described the experience.Since being uploaded onto YouTube Monday, the video has been video nearly 600,000 times.Howls play a key role in a wolf pack. Some experts have suggested that the vocalization strengthens the bonds of the group, and chorus howls can end feuds between wolves, according to the PBS show Nova.The act of howling also allows members of the pack spread over a great distance while searching for food to stay in touch because the sound's low pitch and long duration travel well in a forest or across tundra.Although to the untrained human ear all the howls may sound alike, each wolf has its own individual sound which allows pack mates identify one another.