This ridge, interrupted only by major streams, extends south from the Altamaha River in Georgia to the Santa Fe River in Florida, a distance of 130 miles. It is an ancient barrier beach formerly many miles off-shore in the sea which covered this area during the Pleistocene, or last Ice Age. The top of the ridge is now about 160 feet above sea level and formed a natural trail way for the Indians and early white settlers through the coastal lowlands.