The nine 18 m (60 ft) diameter spheres are linked by 3 m (10 ft) diameter tubes, enclosing stairs and escalators. The spheres form the shape of a unit cell of an iron crystal magnified 165 billion times. Only five spheres are open to the public, containing exhibition halls and other public spaces.
Originally intended to be dismantled once the Fair was over, it was allowed to remain, though by 1979 it was looking rather tired and the original Atomium '58 guide book was still on sale. The structure was renovated soon after the turn of the century. Views from the domes include the Heysel Stadium, scene of the 1985 disaster that cost the lives of 39 football fans. A decade after the disaster, the stadium was rebuilt and renamed King Baudouin Stadium, after the Belgian king who had died two years previously.
