CHESTER COUNTY, Pa (CBS) — Deep in the basement of the Franklin Institute, a trove of priceless treasures sit behind a highly secured area. One of the biggest items stored in the area, kept underneath a heavy protective cover, is a 75,000 cubic square foot antique hot air balloon.

The Institute has one of the most unique connections to that hot air balloon and the city of Philadelphia.

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It was commissioned in 1981 by Constance Wolf, a renowned avid aviator and balloonist of her time.

credit: National Balloon Museum

“She had this particular balloon made to celebrate Billy Penn’s landing,” said Susannah Carroll who is the Assistant Director of Curatorial at the Institute, said. “This balloon actually has an image of William Penn on the balloon.”

Earlier in June, museum inspectors unfurled the delicate balloon ahead of the Chester County balloon festival, where it is on display so people can learn the region’s long history of ballooning.

“Benjamin Franklin witnessed one of the first balloons flights in an air balloon in France when he was there. The first flight in America was in the 1700s,” Carroll said.

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That very first flight happened in Philadelphia.

Before she died, Wolf donated her balloon to the Franklin Institute for events like the balloon festival. That way, others can learn about her passion and be inspired by the possibilities.

The team from the Franklin Institute will be at the festival all weekend, showcasing some science demonstrations for visitors.

Janelle Burrell