Knoebels Amusement Resort, Pennsylvania
Credit: Bill O'Leary / The Washington Post / Getty Images

A century ago, Pennsylvania was the center of the amusement park universe. Theme parks largely grew out of Pennsylvania Dutch fairs and camps. At Knoebels Amusement Resort, that legacy lives on in hokey haunted houses, 100-year-old carousels, and wooden roller coasters. The park is still family run, and admission is absolutely free. That means that it attracts considerably more locals and has a friendlier, less commercial vibe than many other parks. The place also has notably good food. Try everything, but only after you're done riding the rollercoaster.