With its 18-piece spire, 1WTC stands at 1,776 feet, a direct reference to the year the Declaration of Independence was signed. However, even at this soaring height, it's controversial whether it's the tallest building in the United States. In Chicago, where the Willis Tower holds the national record for tallest building at 1,451 feet, residents have joined the debate over how a skyscraper's true height should be determined; subtracting the spire knocks 1WTC's total height down to 1,368 feet.
Once completed, the tower will contain more than 40,000 metric tons of structural steel. As for the 9/11 Memorial and Museum, according to a tweet from its official account the memorial contains "49,000 cubic yards of concrete, enough to pave more than 200 miles of NYC sidewalks." To put that figure into perspective, 200 miles is the rough equivalent of 4,000 New York City blocks.
Watch a time-lapse video of the tower's construction:
The tower's observation deck, scheduled to open in 2015, was specifically constructed with the memory of the Twin Towers in mind. The deck itself begins at 1,362 feet, and a glass parapet extends to 1,368 feet, the exact height of the South and North Towers.
The tower's observation deck, scheduled to open <a href="http://ny.curbed.com/archives/2013/04/02/15_views_of_1_wtcs_100thfloor_observation_deck.php">in 2015</a>, was specifically constructed with the memory of the Twin Towers in mind. The deck itself begins at 1,362 feet, and a glass parapet extends to 1,368 feet, the exact height of the South and North Towers. <br>
Taking heed of every structural and safety failure of the Twin Towers, developers carefully designed the new tower to be the safest office building in the world. Among 1WTC's unique construction elements are its high-strength concrete, which can withstand seven times more pressure than standard concrete, and its reinforcement steel bars, which are significantly longer than normal (traditionally thumb-sized, 1WTC's rebars are forearm length). Between the dense fireproofing and additional staircase for first responders, the tower well exceeds the city's building safety code requirements.
In addition to the many green features of the 1WTC tower—it was built from recycled construction debris and materials, and will generate power internally—the entire site was specially constructed to collect rainwater to help care for the plaza's greenery, cool the building, and replenish the memorial fountain.
The 9/11 Museum will house stories, videos, and artifacts from the original World Trade Center, including a ticket from the South Tower's observation deck and two tridents from the buildings. The museum is still under construction, though the scaffolding was recently removed to reveal the tridents as pictured.
One World Trade will have 69 floors of office space. Future tenants currently include the U.S. General Service Administration and magazine publisher Condé Nast. Also, below the site, a concourse will offer 55,000 square feet of retail space, connections to eleven New York City subways and PATH trains, and underground access to the ferry terminal on the Hudson River.