- Year: 2009
- Author: Keeling, David J
- Journal Name: Progress in Human Geography
- Journal Number: Vol.33, No.4
- Publisher: SAGE PUBLICATIONS, INC.
- Published Location: London, United Kingdom
A key characteristic of human movement over the past century has been the shift from rural spaces to urban places. As the twenty-first century unfolds, more people now live in urban environments than in rural settings, with dozens of cities housing 10 million inhabitants or more scattered across the globe. Combined with the impacts of economic and cultural globalization, the growth of urban centers has spurred transportation geographers to develop new theories and methodologies to help explain the changing dynamics of accessibility and mobility.