Michael Batty is Bartlett Professor of Planning, Centre for Advanced Spatial Analysis, University College London, 1–19 Torrington Place, London WC1E 7HB; email: [email protected]. Stephen Marshall is a Senior Lecturer in Planning, Bartlet School of Planning, University College London, 22 Gordon Street, London WC1H 0BJ; email: [email protected] One hundred years ago, the first coordinated rea...