This legislation amends the Act of May 17, 1954, which established Gateway Arch National Park, to revise its official boundary . The primary change involves an increase in the park's authorized acreage from one hundred acres to 102.18 acres. The bill also updates the descriptive language within the original act, formally replacing references to "the Jefferson National Expansion Memorial" with "Gateway Arch National Park." To reflect these changes, it mandates the use of a new official map , specifically titled "Gateway Arch National Park Proposed Boundary Revision" and dated August 2023, for delineating the park's revised boundaries.