NEW YORK, N.Y. -- One World Trade Center is now officially the tallest building in the city.
More than a decade after terrorists toppled the original World Trade Center towers, workers at the site installed a steel beam Monday that brings the height of the structure to 1,250 feet.
The steel skeleton of One World Trade now stands slightly higher than the Empire State Building's observation deck.
Port Authority officials say the project has been one of the most complex in the city's history because of both physical challenges and the emotional significance of the site.
"One World Trade Center is much more than an iconic symbol for New York, New Jersey and our region, it is a symbol of liberty and pride for our entire country. It's a symbol of determination and ingenuity," said Port Authority Vice Chair Scott Rechler.
"You always knew you were close to New York when you saw the Twin Towers, now an entire generation will know they are close to New York and know that New York and New Jersey have never stood taller then when they see this building," said Port Authority Executive Deputy Director Bill Baroni.
The agency also said that given the structure's strong central concrete core, running through the tower for the elevators, and separate stairs for the use of firefighters," the new One World Trade Center is an extremely secure building.
"What we've built is not only the tallest skyscraper in New York but it is a tower that will be the safest and most secure in the world," said Port Authority Executive Director Patrick Foye.
It is also hoped the skyscraper will become a symbol throughout the world of American resilience.
"We are very proud of what you have done, in France, of America. We are very very proud of what you have done, congratulations," said a French visitor.
"I'm happy for all of New York and I'm happy for America because it's symbolic for once we get kicked down, we're going to get right back up," said a visitor from New Mexico.
EarthCam.com has released a time-lapse video of the construction.
One World Trade will eventually rise to a height of 1,776 feet. Once complete, it will have 104 floors, including three-million-square-feet of office space.