New York City — The first office tower at Ground Zero, since the September 11, 2001 attacks that destroyed the World Trade Center will open on Wednesday,  marking a comeback for the Lower Manhattan site.

Sheathed in glass, 4 World Trade Center is the smallest of the four main towers on the site where 2,700 people died when hijacked airplanes crashed into the towers. It stands 977 feet tall – a shorter, simpler version of One World Trade Center, which will not be completed until early 2014.

The 72-story building stands empty at the moment, although two government agencies have signed leases for half of the building’s space. Both the Port Authority of New York and New Jersey, which owns the site, and the City of New York committed to the space years ago to help jump start rebuilding efforts.

The skyscraper cost about $2 billion to build, including land lease costs, and was financed with $1.2 billion of tax-free Liberty Bonds and hard-won insurance proceeds.

On Monday, a council of urban designers decided that One World Trade Center, which is being built by Douglas Durst and the Port Authority, would be the tallest building in the United States.

They voted to count its spire in the total height of the building, which will reach 1,776 feet, a number chosen for the year the U.S. Declaration of Independence was signed. The spire on the original twin towers reached 1,727 feet and the Empire State Building’s antenna spire reaches 1,454 feet.