The Geek Atlas recommends a visit to Belgium's Atomium. Bizarrely, the book couldn't include a photograph; Belgian copyright law doesn't allow any reproduction without paying a large fee (which goes to inheritors of someone involved in design and construction -- I guess they've fallen on hard times).
Odd country Belgium.
Instead the atlas refers us to the net, such as this Panoramio image.
According to the Atlas, you can travel through the structure to the globes (iron atoms); one is reserved for school children overnighters.