Today's modern road are designed by civil engineers and incorporate complex underground drainage systems, super-elevation for comfort and safety at high speeds, smooth durable surfaces, and are lighted for night-time travel. These roads are quite different from the early paths and trails originally made by animals (leading from feeding grounds to watering places) and first used by humans as they followed these trails to hunt and explore new lands.
The need for the first manmade roads became important when trade routes began developing between villages. Humans needed to transport themselves, their domestic livestock, and their cargo. Roads are so old that the derivation of the current word is uncertain. Some think it came from the Middle English word "rode", meaning a mounted journey. Shortly after the invention of the wheel in about 3500 BC, roads were built in the Near East. The Romans were some really great road builders. They constructed more than 50,000 miles of roads, primarily to carry soldiers throughout the empire.
The Romans understood that a road must slope slightly from the center toward both sides and have ditches to drain storm water. Hundreds of years ago in England private roads were known as "byways". But certain main roads were "higher" than the adjacent ground, due to earth being thrown from the side ditches toward the center during construction. Because they were "higher" they became known as "highways". (The side ditch on what are now mostly rural or county roads is referred to more technically as a "borrow ditch", but the pronunciation of the word has been slurred for so long here in Texas that most refer to a "bar" ditch.)
In America, travel was primarily by foot or horseback until after the War of 1812. The first hard-surfaced (hand-broken stone and gravel) "turnpike" was 60 miles in length and was built in Lancaster, Pennsylvania in 1795. When the steam locomotive was successfully introduced in 1830 substantial attention to road construction was delayed for decades since the prevailing thought was the railroad was the best way to travel long distances. With the introduction of the automobile after 1900, demand for good roads grew, especially those needed by farmers to get their crops out of the field and to the markets near the railroad.
The first concrete road was constructed in Detroit in 1908. The Federal Interstate Highway System was first envisioned in 1939 and authorized in 1956. ASCE designated it one of the "Seven Wonders of the United States". This modern 42,700-mile network of roads has often been called the greatest public works project in history. We'll discuss it next month.
- John P. Wier, P.E., R.P.L.S., Historical Chair, Fort Worth Branch ASCE, January 2002