Gateway Arch

A 630-foot arch within Gateway Arch National Park, operated by the National Park Service, described as the world's tallest arch and the tallest memorial in the United States. Visitors enter through the west entrance, which faces Fourth Street and the Old Courthouse. An underground visitor centre of 70,000 square feet beneath the arch houses the Museum of Westward Expansion and underwent a $176 million renovation finished in July 2018; the sources disagree on the year that centre was completed, so no year is given. The address above is the national park's mailing address, and no separate street address for the arch's visitor entrance could be confirmed.