CHICAGO -- The largest pipe organ in Chicago sits above the congregation at Chicago's Fourth Presbyterian Church.
The intricate collection of five keyboards and thousands of pipes is like having an orchestra in the balcony -- trumpets, flutes, strings, and more.
This Christmas, many people will hear it for the first time since it was restored, which is no easy task.
It's three-stories high and some pipes are 32-feet tall.
But, Christopher Soer is one of the few people in the country who knows how to do it, and he took WGN photojournalist Mike D'Angelo inside this historic instrument.
WGN's Larry Potash has the story in the video player above