Gateway Arch

The Gateway Arch is the tallest man-made monument in the Western Hemisphere and the defining symbol of St. Louis. Its sweeping 630-foot curve of stainless steel, designed by architect Eero Saarinen, commemorates Thomas Jefferson, the Louisiana Purchase, and the pioneers who set out from here toward the American West. Completed in 1965 on the banks of the Mississippi, it is at once a soaring work of modern sculpture and a monument to the nation's westward expansion.

In the 1930s civic leaders in St. Louis proposed a grand memorial on the Mississippi riverfront to honor the city's role as the 'Gateway to the West' and the westward expansion set in motion by Thomas Jefferson's Louisiana Purchase. A nationwide design competition in 1947-1948 was won by the Finnish-American architect Eero Saarinen, who proposed a single soaring arch of stainless steel.

Saarinen refined the form as a weighted catenary — the shape a hanging chain makes, inverted — 630 feet tall and 630 feet wide at its base. Construction began in 1963, with the two legs built upward independently and meeting at the top with only the slimmest margin for error. The final section was set in place on October 28, 1965. Saarinen, however, had died in 1961 and never saw his design completed.

The completed Arch, clad in gleaming stainless steel, became an instant icon. A unique tram of small pod-like cars carries visitors up through the hollow legs to an observation deck at the summit, with views far across Missouri and Illinois. Part of what was long called the Jefferson National Expansion Memorial — renamed Gateway Arch National Park in 2018 — it is administered by the National Park Service and remains the tallest monument in the Western Hemisphere.