The spire for the top of One World Trade Center is hoisted into place at the top of the building in New York City, on May 10, 2013. The spire has been put in place on One World Trade Center bringing the iconic structure to its full, symbolic height of 1776 feet.

WTC worker Tyler Brown taking in the view after the spire has been installed at the top of One World Trade Center.

The final piece of spire is hoisted in place on top of One World Trade Center, on May 10, 2013 in New York. The addition of the spire, and its raising of the building's height to 1,776 feet, would make One World Trade Center the tallest structure in the U.S. and third-tallest in the world.

Iron workers look at names signed inside of the final piece of the spire on top of the One World Trade Center in New York on May 10, 2013. Workers cheered and whistled as they completed the spire on New York's One World Trade Center on Friday, raising the building to its full height of 1,776 feet and helping fill a void in the skyline left by the September 11, 2001 attacks.

An iron worker takes a photograph of a crane as it places the final piece of the spire on top of the One World Trade Center in New York on May 10, 2013.

The skyline of Manhattan from the top of One World Trade Center on May 10, 2013.

The spire for the top of One World Trade Center is hoisted into place at the top of the building in New York, on May 10, 2013. The State of Liberty is seen bottom right.

Villagers carry a gravestone of an ancestral tomb away from a construction site in Taiyuan, Shanxi province, China on December 18, 2012.

Villagers stand around an ancestral tomb which is being relocated in Taiyuan on December 18, 2012.

Villagers carry coffins containing remains from an ancestral tomb in Taiyuan on December 18, 2012.

Workers lay the foundation for a residential complex around a solitary tomb site in Taiyuan, China's Shanxi province, Dec. 6.

An ancestral tomb, 33 feet high and about 30 square feet, on the construction site of a building in Taiyuan, Shanxi province, in China on Dec. 6.

A resident holds a spittoon as he walks in an area where old residential buildings are being demolished to make room for new skyscrapers in central Shanghai on October 17, 2012.

A man rests on a motorcycle in front of an advertisement in central Shanghai on October 18, 2012. China likely hit the bottom of a seven-quarter long economic downturn between July and September, but the slowest three months of growth since the depths of the financial crisis and a cloudy housing market outlook make recovery prospects tepid.

Fireman remove an injured man from the site of a crane collapse where construction is going on for the 7 line subway extension Tuesday, April 3, in New York. Fire officials say a crane collapse at a Manhattan construction site has injured two people.

Emergency personel remove an injured man from the site of a crane collapse where construction is going on for the 7 line subway extension on April 3, in New York. Fire officials say a crane collapse at a Manhattan construction site has injured two people.

Workers stand at the construction site of homes being built for people displaced by the 2010 earthquake on the outskirts of Port-au-Prince, Haiti. As the hemisphere's poorest country marks the second anniversary of the earthquake that killed some 300,000 people, only about half of the $4.6 billion in promised aid has been spent, half a million people are still living in crowded camps and only four of the 10 largest projects funded by international donors have broken ground.

Jenry Del Rosario, 30, an electrician, checks electric cables on iron rods being used to build homes for people who were displaced by the 2010 earthquake on the outskirts of Port-au-Prince, Haiti.

A woman sweeps the road near new homes being built for people displaced by the 2010 earthquake in Zoranje, Haiti.

An old 80 metre high office building of Kunming municipal government is demolished in directional blasting on Dec. 25, in Kunming, Yunnan Province of China.

Dust rises as an old office building of Kunming municipal government is demolished in directional blasting on Dec. 25, in Kunming, Yunnan Province of China. The area will become a business center after directional blasting.

People walk past the debris after an old office building of Kunming municipal government was demolished in directional blasting on Dec. 25, in Kunming, Yunnan Province of China.

Members of the media walk on the deck of the newly constructed eastern span of the San Francisco-Oakland Bay Bridge during a media tour of the self-anchored suspension span tower on August 29 in Oakland, California. Construction crews have erected twelve foot wide catwalks that connect to the San Francisco-Oakland Bay Bridge self-anchored suspension span's tower and crews will begin to lay the nearly one mile of main cable beginning in early 2012. The bridge has been under construction since 2002 with an estimated price tag of $6.3 billion and will have the world's tallest self-anchored suspension (SAS) tower once completed.

Catwalks hang over a section of the newly constructed eastern span of the San Francisco-Oakland Bay Bridge during a media tour of the self-anchored suspension span tower on August 29 in Oakland, California.

A model of the eastern span of the San Francisco-Oakland Bay Bridge self-anchored suspension span tower is on display inside the CalTrans public information office on August 29 in Oakland, California.

Spectators view a six story building under construction, which collapsed in Nairobi, Kenya, Tuesday June 14, killing at least two people and leaving 14 missing according to officials. The collapsed building is on Nairobi's outskirts, near the international airport.

A six-story building under construction in Kenya's capital collapsed on Tuesday, killing at least two people and leaving 14 missing, officials said. The Red Cross dispatched people to the scene.