Block House No. 1.

This stone fort, which sits on top of the large rock, is the oldest original structure in Central Park (Cleopatra's Needle was created elsewhere and moved). It is one of a number of fortifications built in the area during the War of 1812 (and the only one that survives). Despite the threat that prompted their construction, none of the forts were used in wartime combat and they were abandoned when the war ended, soon after being built. It was later used for ammunition storage.