Gateway Arch National Park

In downtown St. Louis, Missouri, on the west bank of the Mississippi River, the Gateway Arch rises 630 feet in a curve of stainless steel, the tallest man made monument in the United States. It marks the city where the country's westward expansion began, the point from which Lewis and Clark set out. A small tram pod climbs inside one hollow leg of the arch to an observation deck with views reaching 30 miles. Spring and fall bring the mildest weather for the riverfront grounds.