How to Downsize a Transport Network : The Chinese Wheelbarrow | LOW←TECH MAGAZINE
The use of wheelbarrows in combination with specially designed narrow pathways made land transportation in China considerably more efficient than in Europe for a period of almost 1,500 years. Today, critcism on the omnipresent automobile is often ridiculed by saying that we cannot go back to horses and carts, without realizing that the combination of horses and carts is far from evident and not as low-tech as it seems. History clearly shows that an extensive road infrastructure is a very vulnerable thing.
Europe was also left with a deteriorating road network after the demise of the Roman Empire, though the Europeans could buy some time. Because it was sturdier (using piles of stone and concrete rather than the early form of asphalt applied by the Chinese), the Roman road infrastructure remained relatively useful until about the 11th century AD, after which it was largely abandoned. But even before that time, the destruction of bridges and road facilities by the barbarians - or by the locals in order to defend themselves against the barbarians - gradually dimished its usefulness. Lack of maintenance and the plundering of paving stone did the rest. Moreover, the appearance of new towns and capitals (such as Paris) required new routes that did not always coincide with the existing Roman roads.
Contrary to the Chinese, the Europeans did not develop a new vehicle and appropriate infrastructure of paths to make up for the loss of the Ancient highways. New roads appeared during the economic revival of the late Middle Ages, but these were not paved or hardened in any other way. This made them at best inefficient in good weather and nearly impassable when (and after) it rained. Furthermore, because of the absence of foundations, soil erosion caused by heavy rains could wash entire roads away. As a result, the use of carts and wagons all but disappeared in medieval Europe, while nothing else came in place. For people, the options of land transportation again became limited to walking or - only for the rich - horseback riding.