Most European capitals and large cities are surrounded by a ring of motorways in order to meet the high demand for road transport originating from these metropolitan areas.
As a result, dense motorway networks can be found around capitals such as Budapest (120 km per 1000 km2), Wien (109 km per 1000 km2), Madrid (96 km per 1000 km2), Prague and Berlin (both 91 km per 1000 km2).
Since the motorways are generally concentrated in a ring close to the cities, the motorway density often decreases with the size of the area. For example, the motorway density reported for relatively small region of Wien is higher than for the much larger region of Île-de-France, even though the motorway network of Paris is larger per se.
Other densely populated regions with high motorway density include the Randstad region in the western part of the Netherlands: Zuid-Holland (127 km per 1000 km2), Utrecht (125 km per 1000 km2) and Noord-Holland (108 km per 1000 km2).
High motorway densities are also found around the major seaports of northern Europe: the motorway densities of the regions of Bremen (205 km per 1000 km2) with the port of Bremerhaven, of Zuid-Holland with the port of Rotterdam (127 km per 1000 km2) and of Hamburg (114 km per 1000 km2) are among the highest of all European regions.
Another reason for the high density of the motorway network in some central European countries (such as Germany) is the proportionately high volume of transit freight traffic.
The density of motorways on islands is generally low, as islands cannot be reached directly by road. Instead, they rely on sea or air transport. Even so, the motorway density of the Canary Islands appears relatively high at 37 km per 1000 km².
