City Hall Loop was one of the terminus stations for the first subway line to be built under New York City. Opened to the public in 1904, it was beautiful, featuring brass chandeliers, glass tiling and sky lighting to fill it with a warm glow during the day. Unfortunately, the station was closed to the public back in 1945.
Happily, it's still possible and totally legal to catch a glimpse of this wonder from a bygone architectural era. All it takes is a little patience and a ticket to ride the MTA.