One World Trade Center: A view from the top

Members of the news media preview the One World Observatory site, the planned public observation deck under construction on the 100th floor of One World Trade Center in New York, April 2, 2013.

Manhattan is seen from the 100th floor of One World Trade Center in New York, April 2, 2013.

One World Observatory, which is situated more than 1,250 feet over lower Manhattan, will open to the public in 2015 and will include a pre-show theater, multiple spaces that allow for panoramas of the New York City region and numerous dining options. When completed, One World Trade Center will be the tallest building in the western hemisphere at 1776 feet.

A view of One World Trade Center in New York, April 2, 2013.

Members of the news media preview the One World Observatory site, the planned public observation deck under construction on the 100th floor of One World Trade Center in New York, April 2, 2013.

Visitors stand near the windows of the One World Observatory from the 100th floor of One World Trade Center in New York, April 2, 2013.

Members of the news media preview the One World Observatory site, the planned public observation deck under construction on the 100th floor of One World Trade Center in New York, April 2, 2013.

Pedestrians cross the street in lower Manhattan as seen from One World Observatory from the 100th floor of One World Trade Center in New York, April 2, 2013.

The Manhattan Bridge is seen from the One World Observatory from the 100th floor of One World Trade Center in New York, April 2, 2013.

Members of the news media preview the One World Observatory site, the planned public observation deck under construction on the 100th floor of One World Trade Center in New York, April 2, 2013.

A view of Manhattan looking north from the One World Observatory site, the planned public observation deck under construction on the 100th floor of One World Trade Center in New York, April 2, 2013.

Visitors stand near the windows of the One World Observatory from the 100th floor of One World Trade Center in New York, April 2, 2013.

A view of Manhattan looking north from the One World Observatory site, the planned public observation deck under construction on the 100th floor of One World Trade Center in New York, April 2, 2013.

Members of the Port Authority Police stand near windows in the One World Observatory from the 100th floor of One World Trade Center in New York, April 2, 2013.

A tug boat passes under the Brooklyn Bridge as seen from One World Trade Center in New York, April 2, 2013.

Manhattan is seen from One World Observatory from the 100th floor of One World Trade Center in New York, April 2, 2013.

Members of the news media preview the One World Observatory site, the planned public observation deck under construction on the 100th floor of One World Trade Center in New York, April 2, 2013.