Expanding territories: Transport systems past and future

Transport and communication systems are the elements which integrate human activities in space and time. They record our past and will be the important determinants of our future. As a rule, those forms of infrastructure which are used for the movement of people, goods and information diffuse slowly and span many decades from their first introduction to obsolescence. Some of them are almost immortal, even though they often provide different services from those originally intended. Obsolete canals were reused to build railways a century ago in England. Ancient Roman roads have often been buried beneath modern highways. Old harbours are being converted into modern commercial and residential areas