Exclusive | 25 years after 9/11, the World Trade Centers last tower finally rises

Larry Silverstein was 70 years old when he took title to the Twin Towers, posing for photos with a giant set of cardboard keys.He figured he had finally arrived — and he could start thinking about retirement.

Seven weeks later, on Sept.11, 2001, his optimistic site became one of tragedy.Now 95, Silverstein still goes to his office every day at 7 World Trade Center, the first tower his company rebuilt, and watches the final piece of his 25-year project rise a few blocks away.“New York has always been a city that refuses to walk away from a challenge,” Silverstein told The Post.

“After 9/11, I made a promise to New Yorkers that we would rebuild the World Trade Center, commemorate those we lost [and] restore commerce to Lower Manhattan.”Ground broke in July on 2 World Trade Center, a 55-story, nearly 2-million-square-foot tower at 200 Greenwich Street that will become American Express’s new global headquarters. It is the last commercial office building called for in the original master plan; when it opens in 2031, every site on the 16-acre campus will be finished or under construction, according to the Port Authority of New York and New Jersey, which owns the land.“Every one of these other buildings kind of had to be built first,” Dara McQuillan, chief marketing and communications officer for Silverstein Properties, told The Post, explaining why 2WTC is only now going vertical.Money was the first obstacle.Silverstein bought the lease on the Twin Towers for $3.2 billion in 2001, then spent five years fighting more than 20 insurance companies over payouts, a fight that only ended after then-Gov.

Eliot Spitzer threatened to bar insurers from doing business in New York if they didn’t pay up.That money, plus federal Liberty Bonds, went first into 7 World Trade Center, One World Trade Center and 3 and 4 World Trade Center — necessary steps to prove the site could attract tenants, before anyone would finance another speculative tower.Bureaucracy comp...