"Jefferson National Expansion Memorial in Saint Louis, Missouri. This amazing monument was designed by Finnish architect Eero Saarinen with the contribution of the structural engineer Hannskark Bandel back in 1947. The arch was finally built between 1963 and 1968. It is tall enough at 630 feet/192 meters and as wide as 630 feet/192 meters at base level. Legs are 54 feet/16 meters at the base yet only 17 feet/5.20 meters at the top. Believe it or not, there is a tram to carry passengers to the top, with an amazing observation deck featuring unique overview of Saint Louis. Just a marvel of engineering! Be aware: the ride to the top is done thanks to very small wagon. Avoid it if you are somewhat claustrophobic."