If you want to go places in a car, it's important to have a road. That is just a fact. Humans have been building roads since ancient people crossed well-worn paths between settlements — like the 440-mile (708-kilometer) Natchez Trace that runs between Mississippi and Tennessee.
But these days, our roads are much longer, some of them traversing thousands of miles of terrain that would be nearly uncrossable without them. Here are the nine longest roads humans have built to date.