The Atomium is a monument in Brussels

Brussels

Brussels , officially the Brussels Region or Brussels-Capital Region , is the capital of Belgium and the de facto capital of the European Union...

, originally built for Expo '58

Expo '58

Expo 58, also known as the Brussels World’s Fair, Brusselse Wereldtentoonstelling or Exposition Universelle et Internationale de Bruxelles, was held from 17 April to 19 October 1958...

, the 1958 Brussels World's Fair

World's Fair

World's fair, World fair, Universal Exposition, and World Expo are various large public exhibitions held in different parts of the world. The first Expo was held in The Crystal Palace in Hyde Park, London, United Kingdom, in 1851, under the title "Great Exhibition of the Works of Industry of All...

. Designed by André Waterkeyn

André Waterkeyn

André Waterkeyn was a Belgian engineer, born in Wimbledon, best known for creating the Atomium.Waterkeyn was the economic director of Fabrimetal, a federation of metallurgical companies when in 1954 he was asked to design a building for the 1958 World Expo that would symbolize Belgian engineering...

, it stands 102 metres (335 ft) tall. It has nine steel

Steel

Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

 sphere

Sphere

A sphere is a perfectly round geometrical object in three-dimensional space, such as the shape of a round ball. Like a circle in two dimensions, a perfect sphere is completely symmetrical around its center, with all points on the surface lying the same distance r from the center point...

s connected so that the whole forms the shape of a unit cell of an iron

Iron

Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

 crystal

Crystal

A crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. The scientific study of crystals and crystal formation is known as crystallography...

 magnified 165 billion times.

Tubes connect the spheres along the 12 edges of the cube and all eight vertices to the centre. They enclose escalator

Escalator

An escalator is a moving staircase – a conveyor transport device for carrying people between floors of a building. The device consists of a motor-driven chain of individual, linked steps that move up or down on tracks, allowing the step treads to remain horizontal.Escalators are used around the...

s connecting the spheres containing exhibit halls and other public spaces.