In South Carolina, that line is called the Orangeburg Scarp. It is where the coastline used to be millions of years ago. Driving westward from the coast, you'

In South Carolina, that line is called the Orangeburg Scarp. It is where the coastline used to be millions of years ago. Driving westward from the coast, you'll encounter a series of steep hills these days as you gain elevation. If the Garner-Edisto fault line ever lets go in a major way, you want to be on the western side of it, to avoid the anticipated Tsunami.