Built in 1806 and substantially altered in 1881, the ceremonial entrance to the U.S. Navy's oldest shore establishment is an example of Greek Revival and Italianate architecture.

Three years later, President Thomas Jefferson chose Latrobe to design a dry dock and ship repair facility for what was to become an active and strategically located naval yard.

Plans for the Main Gate were approved by Secretary of the Navy Robert Smith in 1805, and construction lasted from that year until 1806.

Thornton predicted that "not until extinction of time will such an arch ever be made again", but the Greek Revival style became popular with 19th-century American architects.

The Marines manning the Latrobe Gate are responsible for raising and lowering the American flag outside the Chief of Naval Operations' (CNO's) house.