The Gateway Arch is the architectural landmark of St. Louis. It was designed by Finnish architect Eero Saarinen, and completed in 1965 to commemorate the westward movement of pioneers and settlers from the city in the 19th century. The structure is 192 m tall and also 192 m wide at the bottom, made of stainless steel with reinforced concrete. The surrounding park is called Jefferson National Expansion Memorial, including a Museum of Westward Expansion.