Photo: Brian Doben

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3. Hop Stars
For lots of city girls, double Dutch is as essential a part of childhood as riding a ten-speed is in the burbs. In 2016, when Pennsylvanians Tanisha Rinehardt and Della Burns got nostalgic for their rope-skipping days—and wanted to shed a few pounds—they created a Facebook event called Philly Girls Jump. The duo crossed their fingers and hoped a handful of people would come; instead, thousands signed up. Now PGJ hosts weekly meet-ups at local parks and bigger monthly blowouts complete with food vendors. "We're uniting people with different cultural backgrounds, religious beliefs, social views, and political opinions," says Rinehardt. "When you're jumping, the only thing that matters is fun."