In some cities like London, underground public transport and major sewers and other tunnels have filled up large zones so that the addition of extra routes is onerous or impossible. The development of medical science was largely generated by opening up cadavers and understanding the normally unseen organs. Cities in the late 20th century are still much misunderstood in their circulatory and other bodily functions. They work in often clumsy and inefficient ways which can damage economic viability and inhibit beneficial change. We need to attend more anatomy lessons.
Movement is a measure of the energy and vitality of a human society.
The movement is not just of people and vehicles and goods at the surface but of water, sewage, energy and communications below ground. In the last two hundred years and especially in the last decade our demands for movement, not just of the vehicular sort, have expanded dramatically. The traditional street by good fortune has accommodated sewers and water mains, electricity and gas, cables for communication and now in some areas hot and chilled flows from combined heat and power stations. In some cities like London, underground public transport and major sewers and other tunnels have filled up large zones so that the addition of extra routes is onerous or impossible. The problem is exacerbated by our tendency to use piles for the foundations of buildings.