Built in 1931, the George Washington Bridge is approaching the century mark.

Keeping the world’s busiest bridge open to commuters, walkers and bikers takes constant maintenance and every now and then a major restoration project.

Currently, the bridge is in the midst of a $2 billion makeover. The Port Authority of New York and New Jersey calls it “Restoring the George.”

Already, 592 vertical steel suspension ropes connected to the roadway were replaced for $452 million. The main cables were cleaned, there’s new lighting and the new Southwalk was opened. It's a pedestrian-only walkway across the George Washington Bridge. All of the bikers that like to cross the bridge are supposed to use the Northwalk that was put in place two or three years ago.

The Port Authority reports that a combined 650,000 bikers and walkers crossed the bridge last year.

“I think that’s beautiful. I think it’s needed. It’ll give more people less stress when they’re walking," said Adrian Peres, of Blauvelt, New York.

Perez walks the bridge from Fort Lee to work in Washington Heights. It is a 25-minute walk that he prefers over a potentially late bus.

Like many walkers, Perez says sharing the narrow Northwalk with bikers can be stressful. Others enjoying the Southwalk for the first time are hopeful bikers keep to their side of the bridge.

“I think I was only 100 feet on the bridge when greeted by a bicycle coming this way, and he was not stopped by the Port Authority police that was there," said John Codd of Kearny.

There’s another project, which the Port Authority approved on Thursday - $117 million for work to secure the ceiling of an area leading to the lower level of the GWB on the Manhattan side. In two separate incidents, concrete fell on cars.

Port Authority commissioners say rock salt and rain caused deterioration.

“We literally went and banged on every piece of concrete we could...and identified that as things we needed to move more quickly," said Commissioner Kathryn Garcia.

That project is separate from the overall restoration, which entails 11 separate projects on the world’s busiest bridge.