Full Metal Jacket

More than 3 million tons of steel were used to build the event venues, the Olympic Village, and Olympics-related public transportation projects in Beijing. The Bird's Nest stadium, which can seat 91,000 people, required 42,000 tons of steel. The grid-like structure of the roof is made of columns that weigh up to 500 tons each. The original design included a retractable roof that would have added 15,000 tons of steel to the $500 million structure, but it was abandoned to reduce cost.