Over the years, road networks, design, width and surface, have been developed for different types of vehicles. Some older roads have been upgraded to suit faster and heavier motor vehicles. In other cases this is not possible or appropriate. Modern highways may suit drivers of modern motor vehicles, but they are frequently criticized and increasingly resisted in residential areas.
The network of streets in most cities was built for slow traffic, and lacks sufficient roadspace or pedestrian sidewalks. Such patterns are obsolete: cities should adopt a parallel system of roads as in Berne, Switzerland, where there is little traffic congestion; or like the alternating one-way avenues of New York and one-way major streets of downtown San Francisco.