Last week's answer

Question: Crossing Deals Gap along the Great Smoky Mountains, a legendary 11-mile stretch of U.S. Route 129 (known as "The Tail of the Dragon") features an incredible 318 banked turns with almost no intersecting roads or driveways. Why does this mountain highway feature such an extreme, continuous series of tight curves rather than long straightaways or gentler mountain sweeps?

Answer: Highway engineers carved the road directly along an 18th-century animal and Native American trail, following the natural contours of the steep mountain ridges without altering the topography.

The route was built along an original track worn down by large herds of buffalo and then was used by Cherokee Native Americans for centuries. The first settles to use the trail were hunters and trappers in the early 1700s. 

Sources: Tail of the Dragon