A soothing sight and sound Friday at the Michigan Central Station in Detroit.

Guest Curtis Frizzell was just visiting the station to take some pictures of the architecture, when he was surprised by whimsical singing.

A group of nuns had taken center stage and began a beautiful ballad of harmonious singing.

Turns out the nuns are Dominican sisters out of Ann Arbor who were just in line for visit. A station employee found out the sisters were actually a choir, and they agreed to a spur of the moment song.

Frizzell said "it's something that hasn't been heard in over thirty years" at the station.

Check out the nun's impromptu performance for yourself: