Old Post Office Building

Old Post Office (OPO)
Open to the public.

The National Park Service provides daily tours of the Old Post Office Tower (Hours of Operation: 9am - 4pm).

1100 Pennsylvania Ave, NW
Washington, DC 20004

Completed in 1899 as the headquarters for the rapidly growing U.S. Postal Service and the office of the Postmaster General, the Old Post Office was built in a downtown business area on Pennsylvania Avenue very different from the "Federal Triangle" enclave of monumental buildings constructed around it by the federal government in succeeding decades. GSA now leases the building for hotel use.

Last Reviewed: 2022-09-27