Fort Lee, N.J. — The George Washington Bridge will greet commuters tomorrow with a sight they never see — unless they work holidays.

Fort Lee, N.J. — The George Washington Bridge will greet commuters tomorrow with a sight they never see — unless they work holidays.

The bridge will turn on its tower lights and fly its famous American flag from dawn to dusk in a Frank Sinatra if-you-can-make-it-here kind of moment, its 75th birthday.

The party, however, will be small in comparison to the one that the Port Authority of New York and New Jersey organized for 5,000 people to open the bridge to traffic in 1931. And it won't even be on what is now the world's busiest bridge for fear of snarling traffic.

Fourth-graders from elementary schools in Fort Lee and across the Hudson in Washington Heights will gather in a small park on a bluff overlooking the bridge to present the birthday cards they made for the occasion, sing "Happy Birthday" and blow out the 75 candles on the cake.

Fort Lee and Washington Heights, of course, were strategic posts for Washington's soldiers assigned to protect the Hudson River in the Revolutionary War and the two forts ultimately played a pivotal role in the Battle of New York in 1776 — and suggested a name for a bridge 150 years later.

"I don't know if anybody will notice, but we got the painting done in time," said Bob Durando, the bridge's general manager. "You know, the painting of the towers that's been going on the past five years."

The $62 million project, like almost everything else about the bridge, is in the superlative stratosphere. Ten layers of old lead paint were removed from 2.2 million square feet of tower and three layers of new zinc-epoxy-urethane paint, 49,300 gallons of gray, were applied.

"The bridge is a remarkably busy place," said Durando, a career Port Authority employee. "There's always, always, always, something going on here. The maintenance is constant — now, we're getting ready to replace the deck for the second time in 75 years — but the Port Authority's commitment to public safety and security is constant, too. Everything we have here is cutting-edge, and we do it all with toll revenue, not with tax dollars."

Othmar Ammann, the Port Authority engineer who designed the bridge, obviously expected that the bridge would be around in 75 years. Why else would he have overengineered it to support a second and a third level? The second level became a reality in 1962, but the third level?

"We talk about it every once in a while, but the problem is, what do we do with the roads on either side, how do we get traffic on and off the bridge," said Durando.

The Port Authority, as a result, has turned away from bridge-building to so-called intelligent transportation systems to keep traffic moving. E-ZPass, for example, not only boosts the capacity of toll booths to process traffic but also supplies real-time estimates of how long it will take to cross the bridge.

"Technology has been our friend in protecting the people who use the bridge and the bridge itself," said Mike Barry, a Port Authority police officer assigned to the bridge. "What we've done since 9/11, the money invested in equipment, manpower, training, isn't really visible to people, but it's there."