The Park Avenue Armory, also known as the 7th Regiment Armory, is a historic armory for the U.S. Army National Guard at 643 Park Avenue in the Upper East Side neighborhood of Manhattan in New York City, United States. Designed in the Gothic Revival style by Charles Clinton for the 7th New York Militia Regiment, the Park Avenue Armory was completed in 1880, with two expansions in the early 20th century. The building and its interior are New York City designated landmarks, and the structure was made a National Historic Landmark in 1986. Since 2006, it has been the home of the Park Avenue Armory Conservancy, which leased the building for 99 years from the New York state government. The 53rd Digital Liaison Detachment of the New York Army National Guard, the Veterans of the 7th Regiment, the Knickerbocker Greys cadet corps, and the Lenox Hill Neighborhood House also occupy parts of the armory.

Park Avenue is a boulevard in New York City that carries north and southbound traffic in the boroughs of Manhattan and the Bronx. For most of the road's length in Manhattan, it runs parallel to Madison Avenue to the west and Lexington Avenue to the east. Park Avenue's entire length was formerly called Fourth Avenue; the title still applies to the section between Cooper Square and 14th Street. The avenue is called Union Square East between 14th and 17th Streets, and Park Avenue South between 17th and 32nd Streets.