The main purpose of this legislation is to update the boundaries of the Gateway Arch National Park in St. Louis, Missouri. The goal is to slightly increase the size of the park to better reflect its current layout and management needs. Key provisions of the legislation include changing the official size of the park from 100 acres to 102.18 acres. This adjustment is based on a new map that outlines the proposed boundary revision, which was created in August 2023. The bill specifies that the previous map reference from January 1992 will be replaced with this updated map.