Atomium at 50 continues attracting visitors At first glance the Atomium looks like an UFO. The monument's nine, oversized metal spheres are not that pretty, but they have fascinated visitors for 50 years. More than anything else, Atomium's structure excites visitors. It stretches 102 metres into the sky, appearing effortlessly to support the steel, glass and aluminium. Atomium, which represents an iron molecule magnified 165 million times, was the sensation of the 1958 Brussels World's Fair. This year its operators want to revive the 1950s as the monument marks its golden anniversary.