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Highways The Location Design Construction and Maintenance of Road Pavements

Everybody travels, whether it be to work, play, shop, do business, or simply visit people. All foodstuffs and raw materials must be carried from their place of origin to that of their consumption or adaptation, and manufactured goods must be transported to the marketplace and the consumer. 

Highways The Location Design Construction and Maintenance of Road Pavements

Historically, people have travelled and goods have been moved: 

(1) by road, i.e. by walking and riding, using humans and various beasts to carry goods or to pull sleds, carts, carriages and wagons, and (since the late 19th century) using cycles and motor vehicles such as cars, buses and lorries; 

(2) by water, i.e. using (since early times) ships and boats on seas, rivers and canals;

(3) by rail, i.e. initially using animals (in the early 19th century) and then steam-, oil- or electric-powered locomotives to pull passenger carriages and goods wagons; and 

(4) by air, i.e. using airships and aeroplanes (in the 20th century).

Whilst the birth of the road is lost in the mists of antiquity, there is no doubt but that the trails deliberately chosen by early man and his pack animals were the forerunners of today’s road. As civilization developed and people’s desire for communication increased, the early trails became pathways and the pathways evolved into recognized travelways. Many of these early travelways – termed ridgeways – were located high on hillsides where the underbrush was less dense and walking was easier; they were also above soft ground in wet valleys and avoided unsafe wooded areas.

The invention of the wheel in Mesopotamia in ca 5000 BC and the subsequent development of an axle that joined two wheels and enabled heavy loads to be carried more easily, gave rise to wider travelways with firmer surfacings capable of carrying concentrated loads, but with less steep connecting routes down to/up from valleys and fordable streams. Thus trackways evolved/were created along the contours of lower slopes, i.e. they were sufficiently above the bottoms of valleys to ensure good drainage but low enough to obviate unnecessary climbing. The trackways eventually became well-established trade routes along which settlements developed, and these gave rise to hamlets and villages – some of which, eventually, became towns and cities.

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