Transportation Structures:
Evolution / Chronology

Observations

An esoteric, detailed analysis of a mundane, commonplace thing: roads...

Evolution / Chronology of Route Structures

Vernacular Roads to Engineered Roads : a gradient from no design and construction...to massive design and construction involvement. Bridges are a good indicator of the level of infrastructure.

A theoretical route could evolve through the following progression of development. Dates are exemplary of Ohio, especially south-central Ohio. Each era lasted far beyond the next era; many are still running in remote areas.

Aboriginal Era - 10,000 ybp

• Foot travel.
  No bridges.

  • Animal Path - No human alteration; no cultural impact

  • Footpath - Foot trail of minor importance

  • Trail - Foot trail of major importance; also almost entirely usable for horses (introduced recently to North America by Europeans). a.k.a. "Warpath."

Pioneer Era - c1774

• Horseback travel.
  Bridges are rare, primitive, and short-lived.

  • War Road - Extant trail or new route that for millitary reasons is for the first time made passable for large groups of people, and vehicles (albeit only small and durable ones). Trails are used when on the desired course, but realignment are made to stay on course or avoid rough terrain; trees are cut, leaving stumps that are short enough for wagons to pass over. Short-term use; no further maintenance (though often kept clear by use or later re-cleared for settlement use). e.g. Todd's War Road; Wayne's route from Cincinnati to Maumee; Hull's War of 1812 route.

  • Trace - Trail marked and slightly improved by Euro-Americans; minimal vegetation cleared, for easier passage on horseback but with no intention for wagons. a.k.a. Pack Road, Blazed Way (though perhaps marked but not improved). e.g. Zane's Trace

Settlement Era - 1795

• Slow, durable horse-drawn vehicles: farm wagons, early coaches.
  Some wooden vehicular bridges (often only glorified trestles; e.g. [Wilmington NC PAS] bridge).

  • "Improved Road" - route adjusted and surveyed from original trail, footpath or trace origin; public involvement in planning and designating; some physical improvement to roadway. a.k.a. Wagon Road. Also used as Post Road: road chosen as an official route for U.S. mail. e.g. early SR 104 (q.v. SR 104 ASC report spinoffs); early "Mud Pike" / US 20 (q.v. ASC report spinoff); "Post Road": SR 161 west from Worthington/Dublin to Urbana ([SR 16 prairie tour]).

Pike Era - c1820

• Faster, lighter horse-drawn vehicles: Connestoga Wagon, stagecoach.
  More bridges; wooden truss & masonry arch vehicular bridges.

  • Pike - A "paved" "Improved Road:" improved beyond basic needs; can be for-profit corporate maintenance of public right-of-way (Turnpikes) or "free" passage public Pikes. e.g. National Road.

    "Paving" types (and the typical progression):

    • Corduroy Road - Logs as road surface; crude.

    • Plank Road - Hewn or sawn timber or lumber pavement; short-lived.

    • Graveled Road (Telford or McAdam method) - hand-crushed and hand-sorted gravel pavement.
      and much later:

    • Asphalt - First solid pavement: gravel bound with tar (= (?) Bituminous Macadam, Tar-Bound Macadam).

Railroad Era - c1850

• Bicycles become popular in late 19th Century, though influence for paved roads for them is mainly urban.

Automobile Era - c1910

• Self-propelled, internal-combustion vehicles available & rapidly becoming popular. (This is the first time that common, popular vehicles commonly travel above ~4 mph.)
  Many vehicular bridges, many of iron & steel; increasingly of concrete.

  • Auto Routes - Consolidation of roads into discrete routes, and later actual roads linked together, signed by symbols and indicated on maps for motoring public in 1910s-1920s. Extant earth or gravel paving used, though soon deteriorating under fast tires when wet.

  • [EarlyAuto Highway] - Solid mineral pavement, some design alterations for higher-speed (>4 mph...~25 mph) travel. e.g Lincoln Highway (US 20), National Road (US 40) in 1910s-1940s, 1920s concrete viaduct in Ohio. Asphalt and concrete paving coming into use.

  • [Mid-Century Auto Highway] - Some limited-access design, more grading for horizontal and vertical curves, for ~35 mph (~45-55 mph). e.g. improvements to US 50 and SR 104 in 1940s-1950s; Olentangy River Road --> SR 315 in Columbus [belongs in next slot]

Freeway Era - c1947

• Autos are more prolific, faster.
  Prolific bridges of all sizes, mostly of concrete.

  • [Highway] - Extant highways improved but not converted into freeways; retain undivided two lanes, access unlimited. e.g. US 50 in Paint Valley; SR 104 near Yellowbud, near Kellenberger Road, etc.

  • Freeway - An auto highway for faster travel (ideally about 50 mph) with solid pavement, divided multi-lanes, limited access, more grading. e.g. Olentangy River Road / old SR 315 in Columbus; I-280 in Toledo; SR 711 and US 422 in Brier Hill, Youngstown. q.v. US 40 book.

  • Suburban Residential - Winding, wide, paved streets built in new outer-urban developments (sidewalks optional).

Interstate Freeway Era - c1970

• Autos (and freight trucks) indispensible, ubiquitous, high-speed.
  Super bridges: the bridge roadway feel and treatment is indistiguishable from solid road. Size almost no limit.

  • Superhighway (Modern [Interstate] Freeway) - Solid pavement, multi-lane, limited access, generous berm and right-of-way, much grading; (originally) designed for speeds of 75 mph. e.g. I-71, I-70, I-75; I-270 in Columbus

  • [Arterial Suburban Streets/Roads] - Existing rural roads enveloped with urban growth are rebuilt wider and with parallel service/access roads to deflect non-through traffic. e.g. Bridge Street, Chillicothe; Morse Road and I-161, Columbus; Detroit?

...also the evolution of the parking lot? (cf. gas station development)