PORTLAND, Ore. — The Agnes Flanagan Chapel is a 16-sided architectural marvel that seats 650 under stained glass windows depicting the book of Genesis.

In the early 1970s, it was also a big, conical quandary. Chapels aren't really chapels unless they have an organ, and the newly minted structure at Portland's Lewis & Clark College was in need.

But those 16 sides presented a hitch. How do you fit an ordinary pipe organ into a building that's anything but?

You don't. So the college went in search of an organ builder willing to try something different. Several, said organ curator Lee Garrett, backed away. But the world-renowned Larry Phelps took the challenge.

Phelps' solution was to build something to fit the chapel, and the idea for the world's only circular pipe organ was born. Unlike a traditional pipe organ – played by someone sitting in front of the instrument as the notes flow through the pipes into the audience – this organ is suspended from the ceiling, allowing the music to reflect off the floor and into the crowd.

"One of the challenges of playing any organ is that no two are identical," said Garrett, a professor emeritus of music at Lewis & Clark. "Here, it's unusually difficult because the organist plays from the balcony and the organ is suspended from the ceiling."

The electro-pneumatic instrument and its 4,000 pipes turned 40 last year. It has played to graduations, memorials and holiday celebrations.

Players use three keyboards, called manuals, along with pedals and a series of knobs, to create a range of sound. With a couple of setting changes, the organ can be altered to mimic other instruments, like a trumpet.

Now, it serves as a recruiting tool for the college's music school.

"It's one of the most unusual instruments in the country, if not the world," Garrett said.

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  • The circular pipe organ is shown at the Agnes Flanagan Chapel Tuesday, June 12, 2012, on the campus of Lewis & Clark College, in Portland, Ore. The Agnes Flanagan Chapel is a 16-sided architectural marvel that seats 650 under stained glass windows depicting the book of Genesis. In the early 1970s, it was also a big, conical quandary. Chapels aren't really chapels unless they have an organ, and the newly-minted structure at Portland's Lewis & Clark College was in need. (AP Photo/Rick Bowmer)

  • Organist Christopher Keady plays the circular pipe organ at the Agnes Flanagan Chapel Tuesday, June 12, 2012, on the campus of Lewis & Clark College, in Portland, Ore. The Agnes Flanagan Chapel is a 16-sided architectural marvel that seats 650 under stained glass windows depicting the book of Genesis. In the early 1970s, it was also a big, conical quandary. Chapels aren't really chapels unless they have an organ, and the newly-minted structure at Portland's Lewis & Clark College was in need. (AP Photo/Rick Bowmer)

  • Organist Christopher Keady plays the circular pipe organ at the Agnes Flanagan Chapel Tuesday, June 12, 2012, on the campus of Lewis & Clark College, in Portland, Ore. The Agnes Flanagan Chapel is a 16-sided architectural marvel that seats 650 under stained glass windows depicting the book of Genesis. In the early 1970s, it was also a big, conical quandary. Chapels aren't really chapels unless they have an organ, and the newly-minted structure at Portland's Lewis & Clark College was in need. (AP Photo/Rick Bowmer)

  • Organ pipes are suspended from the ceiling at the Agnes Flanagan Chapel Tuesday, June 12, 2012, on the campus of Lewis & Clark College, in Portland, Ore. The Agnes Flanagan Chapel is a 16-sided architectural marvel that seats 650 under stained glass windows depicting the book of Genesis. In the early 1970s, it was also a big, conical quandary. Chapels aren't really chapels unless they have an organ, and the newly-minted structure at Portland's Lewis & Clark College was in need. (AP Photo/Rick Bowmer)

  • Organist Christopher Keady plays the circular pipe organ at the Agnes Flanagan Chapel Tuesday, June 12, 2012, on the campus of Lewis & Clark College, in Portland, Ore. The Agnes Flanagan Chapel is a 16-sided architectural marvel that seats 650 under stained glass windows depicting the book of Genesis. In the early 1970s, it was also a big, conical quandary. Chapels aren't really chapels unless they have an organ, and the newly-minted structure at Portland's Lewis & Clark College was in need. (AP Photo/Rick Bowmer)

  • Organist Christopher Keady sits at the circular pipe organ at the Agnes Flanagan Chapel Tuesday, June 12, 2012, on the campus of Lewis & Clark College, in Portland, Ore. The Agnes Flanagan Chapel is a 16-sided architectural marvel that seats 650 under stained glass windows depicting the book of Genesis. In the early 1970s, it was also a big, conical quandary. Chapels aren't really chapels unless they have an organ, and the newly-minted structure at Portland's Lewis & Clark College was in need. (AP Photo/Rick Bowmer)

  • Sheet music is shown on the circular pipe organ at the Agnes Flanagan Chapel Tuesday, June 12, 2012, on the campus of Lewis & Clark College, in Portland, Ore. The Agnes Flanagan Chapel is a 16-sided architectural marvel that seats 650 under stained glass windows depicting the book of Genesis. In the early 1970s, it was also a big, conical quandary. Chapels aren't really chapels unless they have an organ, and the newly-minted structure at Portland's Lewis & Clark College was in need. (AP Photo/Rick Bowmer)

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