A number of patterns and trends can be discerned concerning urban structure and travel using the available aggregate datasets in Great Britain. There are limitations in what can be done based on existing datasets – the National Travel Survey, for example, can usually only be analysed at the regional level or higher, for sample size reasons. More details are found in the background technical report.
There has been huge growth in aggregate passenger distance over time (1952-2007) – the ‘mobility explosion’, with a dominance of the private car in mode share terms. Much of this growth has been on inter-urban roads.
Population Density and Annual Average Distance Travelled
- There is broadly an inverse linear relationship, where increased density is associated with reduced travel distance, particularly by car. Distance by public transport increases with density, particularly over 30 persons per hectare (pph). Walking distance is similar over all distances except the highest – over 50 pph.
- Great Britain: car drivers average 3,660 miles per annum (51% mode share), relative to an average density of 2.5 pph.
- London: a lower average distance by car at 1,876 miles per annum (35% mode share), relative to a higher average density of 46 pph.
Settlement Size/Area Type and Annual Average Distance Travelled
- There is broadly an inverse linear relationship within the urban area category with increased average distance travelled as settlement size decreases.
- The largest differential is between inner London (an average of 4,673 miles per annum) and rural areas (an average of 9,806 miles per annum).
- Outer London performs more like the other metropolitan areas in terms of average distance travelled.
- The highest average distances travelled (in non-rural areas) are in the smaller urban areas, particularly those with a population of under 25,000.
Public Transport Accessibility and Annual Average Distance Travelled
- Average annual travel distances reduce as public transport accessibility (accessibility to a composite of key services) increases over the 70% threshold, with the exception of remote areas with poor accessibility where travel distances are also relatively low. Areas with very good levels of accessibility (over 80%) have lower levels of car use and higher proportions of public transport, walking and cycling.