Since 1682, the first planned city in the United States, Philadelphia, was and is a city of firsts in America:

The first stock exchange, penitentiary, Thanksgiving Day parade, hot-air balloon flight, and even the birthplace of the Slinky.

An exhibition showcasing Philadelphia's history, "About Philadelphia: A City of Firsts," was unveiled Thursday by Mayor Nutter at Philadelphia International Airport's Terminal A-East.

Photographs documenting the city's historic markers in the tapestry of America will be on display for a year.

But first things first: An airplane ticket is needed to view the free exhibit.

"Through this exhibition, we hope to provide passengers with something more than just a space of transit; we hope to provide them with a human touch," said Mark E. Gale, CEO of Philadelphia International Airport. "The exhibition is also a chance to showcase the city and give passengers a chance to see the city and, hopefully, attract them to return."

For a city with so many mobsters who "sing" to authorities, it is only fitting that we have the oldest continuously operated grand opera house in the country (the Academy of Music).

The city is a flower powerhouse, with the first botanical garden, in 1728 (Bartram's Garden), and the first Flower Show, in 1829.

It is also a center of learning and technology, with the nation's first natural sciences museum, in 1812 (the Academy of Natural Sciences of Drexel University), the first computer (the 30-ton ENIAC at Penn), in 1946, and the first demonstration of the telephone, in 1876.

The city's status as a health-care mecca was established early on, with the nation's first hospital (Pennsylvania), medical school (Penn), women's medical school (now part of Drexel), children's hospital (CHOP), and the first genetic link to cancer (the Philadelphia chromosome), discovered by researchers at Penn and Fox Chase Cancer Center.

Of course, the city is also the source of many things that make people less healthy, if happier, such as the first soda, Dr. Physick, in 1807, the first Girl Scout Cookies, in 1933, and the oldest ice cream company, Bassetts, in 1861.

Members of the Bassett family attended the unveiling. "We're incredibly proud to be here," said Michael Strange, president of Bassetts, a fifth-generation member whose son now works for the company. "I am also very proud we've got the sixth generation coming along."

Of course, many Philadelphia distinctions have been given away, including the first Continental Congress and the first capital of the United States, both in 1774, and the first Supreme Court, in 1791.

But many remain. Of more than 80 firsts, photographs of 59, some on digital display, some printed and framed, are arranged from 1683 to 2013.

The exhibition starts with a 1682 map of the city by Thomas Holme, the first surveyor general of Pennsylvania.

It concludes with what city leaders call the nation's first and most comprehensive lesbian, gay, bisexual, and transgender (LGBT) rights law in, 2013.

This year marks the 50th anniversary of the first Annual Reminder Day pickets, a demonstration in 1965 at Independence Hall that is also noted in the exhibit, said Leah Douglas, the airport's exhibitions director.

"We're very proud" that LGBT rights have improved, said Mark Segal, an airport board member and publisher of Philadelphia Gay News. "Philly is the most LGBT-friendly city in America. We're different from any other city because the LGBT community is very integrated. No other city, not even San Francisco or New York, can claim that."

Philadelphia was the first city in the nation to offer tax incentives to companies that expand health benefits to same-sex partners, in 2013.