Gateway Arch in St. Louis#
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Licensed under PD
Built between 1963 and 1965 (but not opened to the public until 1967), the stainless steel-sheathed structure is hollow to accomodate a unique tram system that takes visitors to an observation deck at the top.
Both the height and width of the arch are 192 m (630 ft). The structure is the tallest monument in the United States and the tallest stainless steel monument in the world.