Famously connecting Chicago to L.A., this 2,400-mile highway spawns America's signature roadside architecture and attractions. Though the 100-year-old Route 66 was ultimately bypassed by the modern interstate highways, you can still drive through it and visit the major cities and quaint towns along the way—including a few ghost towns. On the roads' westernmost section, you’ll also be quite close to must-sees like the Grand Canyon. Set aside at least two weeks for your road trip through the vast American heartland. Guidebooks and apps will also make your journey a lot more informative and fun. – Tripadvisor