How They Built the World’s Most Famous Landmarks

Eero Saarinen’s stunning design for the Gateway Arch won a nationwide competition in 1947, but construction didn’t begin until February 1963. The project was an engineering marvel. Each leg was built up separately, a triangular tube of steel growing taller day by day. The whole city of St. Louis watched, wondering if the two sides would actually meet. In October 1965, with crowds gathered below, the final keystone piece was carefully hoisted into place, completing the curve. It is still the tallest arch in the world.