Before Columbus, most movement from place to place was via paths or animal trails although the Amerindians, particularly in the area of Mexico, did build some elaborate stone roads. When the European settlers arrived in America and introduced their wagons into the wilderness, they quickly found the need to widen the paths and animal trails to accommodate the wider track of the wagons. Part of the lore of American history is the work of the young George Washington as a surveyor laying out a road from the piedmont of the east coast into the Ohio country across the mountains. The old paths had a near one-to-one human scale: the path was usually about as wide as one person. Animal trails, particularly those trod out by the bison, were sometimes wider. In the south there are several long routes know by the name of "trace" which are now highways that were once animal trails. The familiar Natchez Trace of Tennessee and Mississippi lore is one of these.
Early roads were technologically simple. Roads were cleared by felling trees right and left to drop them away from the road. In a few places corduroy or plank roads were created by cutting small trees and using them for a road surface or buy actually creating a smooth artificial road surface with sawed planks nailed across supporting timbers or logs beneath. As settlement pushed westward through the Appalachian mountains, the routes of roads often followed the banks of rivers. River banks afforded a level area with good access to water and game animals for sustenance along the way. In a few areas, for instance in some sections of the French Broad, Holston, and Clinch rivers used for entry into upper East Tennessee, the road was the river bottom itself. In these places the flat bottom of the shallow river offered a ready made, firm surface for the passage of wagons. The river bank roads sometimes dipped down into the river for a better bottom and then returned to the bank as the water deepened or as rapids were encountered.
As settlement proceeded through the nineteenth century, road building became an important interest of states and counties. By the end of the century large gangs of convict--road gangs--had replaced indentured and slave labor for building and maintaining roads across the south. Roads were widened, graded, ditched. In the cities, roads were sometimes "paved" by being lined with specially shaped stone--cobble stone--familiar in some older sections of cities. These roads and streets provided a firm if bumpy surface and were certainly an attractive alternative to the mire of muddy holes and puddles roads became during rainy weather. The great advance in nineteenth century road building was the invention of Scottish engineer John McCadam who perfected the technique of a crowned road with a finely packed surface. The twentieth century would see two major developments in road building--the increasing use of petroleum products as a binder or glue to hold together sand or gravel for a road surface and the widespread usage of concrete for road surfaces. The petroleum-based binder was a refinement of McCadam's design which is the origin of the now generic term "macadam" to refer to asphalted roads.
Dirt road. Country Lane. This is a roadway that has been cleared but where the surface is unimproved. Although dirt roads will revert to a natural condition if not used, old dirt roads may persist for decades. Ocasionally in this area one can find the remnant of dirt roads from the nineteenth century. A lane is usually, but not always found in the country. It is a special version of a dirt road that has the added characteristic of a double edge of trees and bushes that define and protect the road. See "Bird Poop and Tree Roots" and the essay, "Lanes." In-town lanes can be seen in Cowan on the left just as one enters the town on the Sewanee highway; another can be seen just off the Boulevard extension in Decherd on the left side of the Co-op store.
Gravel road. In the Franklin County, southern Middle Tennessee, region, these roads are typically dirt roads improved by the addition of crushed limestone. On occasion gravel roads were seriously engineered and a road bed was prepared and loaded with a coarser grade of rock for ballast. Over this ballast might then be layered a filling binder band of clay followed by a finer grade of crushed rock that would consolidate and harden into an all-weather road surface.
Tar Road/Tar and Chip Road. "Black Top" This is the next stage of evolution of the gravel road. Tar is spread on the road surface in a thin layer and into the surface of the liquid tar is shoveled sand or gravel. The tar has the effect of sealing the surface so that less water leaks into the roadbed and of holding the sand or rock in place. The embedded gravel gives a rough texture to the road and causes a bumpy ride for vehicles. Most gravel and tar roads in the county are about one and a half lanes wide.
"Asphalt" Road/macadam road. This is the real "paved" road of the mid-twentieth century. Generally tar roads do not become asphalted until the traffic load increases on them. Recently many country roads in the Franklin County area have been converted from tar roads to improved paved roads. Paved roads offer a finer, smoother surface for passing vehicles. Generally, paved roads are at least two lanes wide and may be many lanes wide. An important ecological dimension of paving of roads is that rainfall flushes from the road and is channeled by the edge ditches into the local watershed. Paved roads must be seen as often high-volume intermittent streams, and their effect must be calculated in the overall health of any watershed. The road-as-stream effect can be observed in front of McDonald's in Winchester or on University Avenue in Sewanee during any rain shower.
Concrete road. University Avenue in Sewanee is a concrete road. This is a costly but durable form of road construction that saw widest use in portions of the original interstate highway system. The long-term durability, very smooth surface, and bright color of concrete roads made them attractive for many communities. The disadvantage of concrete roads is the difficulty of repairing them. Chips or holes in the concrete persist as severe bumps that cannot be easily mended. In many areas today the old concrete roads are being paved over with macadam surfacing. In the county a recent application of concrete road surfacing can be seen in the ramp portions of the Route 50 connector highway.
Three Lane/Five Lane/Turning Lane. These terms refer to the widening of two or four lane roads to give greater ease for left turns. Where a turning lane is built, it becomes the center lane and is used by cars proceeding in either direction. The outermost lanes are used for continuing travel. The widening of roads to add a center turning lane is a sure sign of development and congestion. The best local example of a turning lane is the center lane of the "boulevard" between Winchester and Decherd. Recently the increased traffic near the Winchester hospital has resulted in the widening of Rt 41 there to include a turning lane. Turning lanes are often confusing to people who are most familiar with the old road where turns were exercised from within the lane of travel. Generally when a road is converted to a center turn lane road, local law enforcement official usually anticipate a period of accidents until people become used to the new lane.
Dual Highway/Interstate Highway/Divided Highway. The new Route 50 connector--connecting Winchester to I-24 at Pelham--is the best local example of this kind of road. These roads have a couple of interesting ecological consequences. Because they produce four miles of edge for every linear mile of road, these roads require more mowing to maintain their outer borders. At the same time, "edge" is a favored habitat feature of many small mammals and birds. Dual highway medians and outer edges become rich wildlife zones. Careful observers can work out the consequence of this on any trip along an interstate highway: these roads across America have become havens for hawks which feed on the small mammals around the edges. The large areas enclosed in the medians of the Interstate Highway system constitute the nation's largest if irregularly shaped forest.
