In addition to the safety features, such as separate staircases for firefighters and blast proof glass, the building will have a green element.
Within the tower, there will be wind turbines that may provide 20 percent of the building's energy.
Symbolic 1776
The skyscraper should be completed at the end of 2008 or the beginning of 2009 at a cost of $12 billion.
Above the offices, the building has a 276 foot spire that takes the tower up to the symbolic height of 1776 feet (541m).
1776 was the year the US declared independence from Britain.
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