It wasn't until August 2002 when an Iranian opposition group broke the news, that the world learned of the existence of the uranium enrichment facility at Natanz in Iran.

The uranium facility which has been built more than fifty feet below ground has been designed with the ability to house up to 50,000 centrifuges. This has caused some concern to the Western powers because as little as 3000 centrifuges are required to create a nuclear weapon.