4. Gravity Hill, Pennsylvania, USA
Gravity Hill, near Bedford, is one of America’s most famous optical illusions. Locals and visitors alike witness vehicles seeming to roll uphill. Markings direct drivers to put their vehicles in neutral—and watch as gravity appears to take a holiday. The enduring legend has spawned rumors of haunted origins, but physics says it’s all about perspective. Check out Atlas Obscura’s coverage: (roadsideamerica.com).