The famous Wanamaker Grand Court Organ was built for the 1904 World’s Fair at a cost of nearly $3 million (in today’s dollars) and was enlarged in 1911-1918 and again in 1924-1930, to its present size of 28,482 pipes. The facade (photo) was restored and regilded in 2019.
The largest organ and musical instrument in the world, it’s currently located at Macy’s City Center in Philadelphia, and is played twice a day, except Sundays. More information about its history and specifications can be found on Wikipedia here.