By Walt Hunter
PHILADELPHIA (CBS) -- A sea of flashing lights, metal barricades and signs floods the Parkway. From the Papal altar, block after block, an entire second city taking shape.
A Papal City with its own reservoir of 1 million donated bottles of water lining the sidewalks and its own broadcast network of giant jumbotrons.
"Philadelphia is the city of block parties, this will be the 'mother of all block parties'," explained Meryl Levitz CEO of Visit Philadelphia.
Above the Northeast Osprey military aircraft and a Marine helicopter normally used to fly top dignitaries like the President practiced takeoffs and landings near the city prison complex which the Pope will visit.
On the ground, National Guard troops, the first of hundreds, arrived to keep watch on streets, with more and more closures coming in the hours ahead.
On the lanes of the Ben Franklin Bridge, fencing was being moved into place to close off traffic lanes as of 10 p.m. Friday night, limiting bridge crossings to pedestrians.
"You want to get into the city by 6 p.m. Friday, that's when most of the restrictions will be in place," stated Mayor Michael Nutter.
City officials say their initial estimates of a one million person crowd and a $417 million economic boost from the Pope's visit remain in place.
One of the main architects of the Papal security plan, Police Commissioner Charles Ramsey, assured residents of other city neighborhoods that they would receive full protection despite the large number of officers assigned to protect the Pope.
And the Commissioner disclosed despite meeting and greeting U.S. Presidents and foreign dignitaries for decades, he has never met the Pope.
As a Catholic, he says, it's a wish he shares with virtually all of the hundreds of thousands who will gather here for largest event of its kind in Philadelphia history.
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