The Atomium, is a landmark building in Brussels, Belguim, originally constructed for the 1958 Brussels World’s Fair (Expo 58). Located on the Heysel Plateau in Laeken, where the exhibition took place. It is now a museum.

Designed by the engineer André Waterkeyn and architects André and Jean Polak, it stands 102 metres (335 ft).

It has enclosed stairs, escalators and an elevator (in the central, vertical tube) to allow access to the five habitable spheres, which contain exhibit halls and other public spaces. The top sphere includes a restaurant which has a panoramic view of Brussels. The building was completely renovated between 2004 and 2006 by the companies Jacques Delens and BESIX.

In the 1950s, faith in scientific progress was great, and a structure depicting atoms was chosen to embody this. The Atomium's nine 18-metre-diameter (59 ft) stainless steel clad spheres depict nine iron atoms.

The construction of the Atomium was a technical feat. Of the nine spheres, six are accessible to the public, each with two main floors and a lower floor reserved for service. Tubes of 3 metres (10 ft) diameter connect the spheres along the 12 edges of the cube and all eight vertices to the centre. The central tube contains the fastest elevator of the time with a speed of 5 m/s (20 ft/s).

Atomium was designed to last six months, it was not destined to survive the 1958 World Expo, but its popularity and success made it a major element of the Brussels landscape.

More Info: en.m.wikipedia.org