On a clear day, the newly opened observation deck on the 57th floor of One Liberty Place offers unhindered views as far as Limerick's steaming nuclear plant cooling towers in the north to Wilmington in the south - with all of Philadelphia's urban bustle packed in between.
What would our city's founders, stuck at pedestrian level, have made of such a panoramic, bird's-eye vista?
"I am beside myself," offered the Benjamin Franklin impersonator hired to stand next to the observation deck's larger-than-life, geodesic bust of Franklin and greet the opening-day crowds Saturday.
Even William Penn, whose statuesque visage smiles down from his 548-foot vantage point atop City Hall, appeared unable to contain his reaction. Viewed from more than 300 feet higher up, poor Billy - back turned, head angled down toward the streets - looked the very picture of dejection. Views that had once been his alone have now been opened to the masses.
The public debut Saturday of the 883-foot lookout at the One Liberty Observation Deck drew a steady stream of paying visitors, a visit from Mayor Nutter, and even a guerrilla-style wedding from two bridegrooms, who quietly rode the elevator to the top of the city's second-tallest building - all the while keeping under wraps their plan to be the first couple to marry in the space.
"This is the first day. This is brand new. This has never happened in Philadelphia before," the mayor told a group from the Boys and Girls Club that he accompanied on the 75-second elevator ride to the top.
Sure, the city has offered up impressive views from on high to the determined for decades: the observation point atop City Hall, the R2L restaurant and lounge on the 37th floor of Two Liberty Place, the Philadelphia Zoo balloon.
But the One Liberty Observation Deck towers over them all and aims to offer a full tourism experience.
In the mid-1980s, construction on the blue glass One Liberty Place at 16th and Market Streets had shattered the city's century-old gentleman's agreement to preserve City Hall's William Penn statue as the tallest architectural point in the city.
(The skyscraper was beaten out in 2008 by the 58-story Comcast Center; it is set to be bested once again by the 1,121-foot-tall Comcast Innovation and Technology Center, scheduled for completion in 2017.)
But over the years, building tenants have made relatively little use of One Liberty's penthouse space. For a time, Cigna used it as a corporate cafeteria. At other points, it sat completely vacant.
Last year, Montparnasse 56, a Paris-based operator of tourism attractions, signed a 20-year lease for the spot with plans to capitalize on recent openings of other public skyscraper viewing decks, including those at the Willis Tower in Chicago and the One World Observatory in Lower Manhattan.
Now, for $19, visitors can soak in unique views by day of Philadelphia landmarks like the bridges over the Schuylkill and the Delaware, the Navy Yard, and the city's sports complex, while marveling at night at the array of city lights below.
At all hours, hometown music acts such as Hall & Oates and Teddy Pendergrass play over the speakers and electronic touchscreens offer visitors a guide to the sights they spot below.
"This is not something most of Philadelphia has had an opportunity to see," said Evan Evans, the observation deck's general manager. "It's a really pretty city at pedestrian level, but from up here, it's just astoundingly beautiful."
Those who partook of the panorama Saturday largely agreed.
"Everything looks so small," said Kristin Mosley, 12, while trying to pick out her home in Nicetown. "Roller coasters aren't even this high."
Her friend 10-year-old Lela Carter, meanwhile, feigned a look of unimpressed detachment. "I've been higher than this before," she said. "On an airplane."
With his wife and college-aged son in tow, William Ivins, of Levittown, joined in what appeared to be the day's most popular activity - snapping cellphone photos.
"I bought a selfie stick just for this," he said. "It's not really my generation's thing, but I even figured out how to use it."
As for the happy bridegroom and bridegroom, Rick Frei, 50, of Fishtown, and Jared Dean, 45, of Powelton Village, exchanged their vows over a view of West Philadelphia in the distance.
Frei said the couple had planned to marry Saturday - their 12th anniversary. Once they realized the observation deck would open the same day, it seemed like kismet.
They grabbed an ordained minister, their two best friends, and hauled tail to ensure they were among the first few to buy tickets to the top.
"We wanted to get married somewhere interesting," Frei said. "We wanted an interesting wedding."
Later, they posed - with the mayor on one side, a Benjamin Franklin impersonator on the other, groomsmen cheering them on with canned champagne, and an unparalleled view of the city sprawling behind them - for what has to be one of the most uniquely Philadelphia wedding photos ever taken.
What: One Liberty Observation Deck
Where: 57th floor of 1650 Market St.
Hours: 10 a.m. to 10 p.m., 365 days a year
Tickets: $19 to $33 for adults; $14 to $28 for children
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