Operating under the authority of the 1935 Historic Sites Act (54 U.S.C. 320101-06) and the National Historic Preservation Act of 1966, as amended (16 U.S.C. 470 et seq.), the National Park Service (hereafter referred to as NPS) administers the National Historic Landmark (NHL) Program, which provides for the identification, documentation, preservation, and interpretation of the Nation's nationally significant historic buildings, sites, objects, structures, and districts. The NPS Heritage Partnerships Program ��� working in cooperation with the Cooperator, the International Boundary and Water Commission, Palo Alto Battlefield National Historical Park, and the City of Brownsville ��� seeks to revise the boundary of Fort Brown NHL in Brownsville, Cameron County, Texas, and prepare a new National Historic Landmark nomination for that site. The purpose for the revision of the existing nomination is to encompass the entire area of (or as much as possible with consenting landowners) the original earth fortification and to consider a larger cultural landscape that also includes sites of additional American and Mexican earthworks. The 1986 NHL nomination only addressed the portion of the fort represented by standing earthworks and included only that portion of the fort within the 80 by 170 yard area designated by the NHL. Recent non-invasive archeological investigations and a cultural landscape study reveal substantial subsurface remains of the fort exist as well as the potential for other works related to the siege of Fort Texas to be contained within the cultural landscape.