The Picatinny Arsenal is an American military research and manufacturing facility located on 6,400 acres of land in Jefferson and Rockaway Township in Morris County, New Jersey, United States, encompassing Picatinny Lake and Lake Denmark. The Arsenal is the headquarters of the United States Army Armament Research, Development and Engineering Center. It is known for developing the ubiquitous Picatinny rail, as well as being the army's center of expertise for small arms cartridge ammunition.
