Price tag for World Trade Centre rises alongside building

Cost for Ground Zero tower estimated at more than $3.8bn, making it worlds priciest office tower
One World Trade Center, the central skyscraper at Ground Zero, stands under construction (All images courtesy of Getty Images)
The price tag for One World Trade has recently been valued at $3.8bn, making it the world's most expensive new office tower
The new figure is up $700m from the latest public estimate
Most of the cost overruns are due to the security measures being taken in the design of the building, which sits on a site that has been bombed twice by terrorists
To offset the costs of One World Trade Center, higher bridge and tunnel tolls have been instated and there has been a reduction in spending on transportation infrastructure
The 1,776-foot skyscraper is expected to be completed at the end of 2013
The One World Trade Center is being built by the Port Authority of New York and New Jersey
Continuing delays also have caused the site in the middle of Lower Manhattan to be boarded up for more than ten years