Short answers, pulled from the story.
The first Madison Square Garden opened on the 11th of February 1879. A leaky roof caused a balcony collapse that resulted in deaths, forcing the demolition of the building in 1890.
Architect Stanford White designed the second Madison Square Garden which stood from 1890 to 1925. New York Life Insurance Company tore down the second Garden in 1925 to build their headquarters.
The current Madison Square Garden sits directly above active railroad platforms at Pennsylvania Station. Robert E. McKee of El Paso, Texas constructed this engineering feat between 49th and 50th Streets on Eighth Avenue.
Madison Square Garden serves as home to the New York Rangers of the National Hockey League. It also houses the New York Knicks of the National Basketball Association.
Billy Joel has performed there 150 times as of July 2024. This figure includes a residency starting in 2014 where he played nearly continuously for a decade.
On the 14th of September 2023, the New York City Council voted 48-0 to renew the operating permit for only five years. This represents the shortest ever granted by the city to the Garden.