Editing City (section)

=== Internal structure ===
[[File:L'Enfant plan.svg|thumb |The [[L'Enfant Plan]] for [[Washington, D.C.]] combines a utilitarian grid pattern with diagonal avenues and a symbolic focus on monumental architecture.]]

[[Urban structure|The urban structure]] generally follows one or more basic patterns: geomorphic, radial, concentric, rectilinear, and curvilinear. The physical environment generally constrains the form in which a city is built. If located on a mountainside, urban structures may rely on terraces and winding roads. It may be adapted to its means of subsistence (e.g. agriculture or fishing). And it may be set up for optimal defense given the surrounding landscape.<ref>Moholy-Nagy (1968), 21–33.</ref> Beyond these "geomorphic" features, cities can develop internal patterns, due to natural growth or to [[urban planning|city planning]].

In a radial structure, main roads converge on a central point. This form could evolve from successive growth over a long time, with concentric traces of [[town wall]]s and [[citadel]]s marking older city boundaries. In more recent history, such forms were supplemented by [[ring road]]s moving traffic around the outskirts of a town. Dutch cities such as [[Amsterdam]] and [[Haarlem]] are structured as a central square surrounded by concentric canals marking every expansion. In cities such as [[Moscow]], this pattern is still clearly visible.

A system of rectilinear city streets and land plots, known as the [[grid plan]], has been used for millennia in Asia, Europe, and the Americas. The [[Indus Valley Civilisation|Indus Valley Civilization]] built [[Mohenjo-Daro]], [[Harappa]], and other cities on a grid pattern, using ancient principles described by [[Kautilya]], and aligned with the [[compass points]].<ref>{{cite journal| first1=Mohan| last1=Pant| first2=Shjui| last2=Fumo| title=The Grid and Modular Measures in The Town Planning of Mohenjodaro and Kathmandu Valley. A Study on Modular Measures in Block and Plot Divisions in the Planning of Mohenjodaro and Sirkap (Pakistan), and Thimi (Kathmandu Valley)| journal=Journal of Asian Architecture and Building Engineering| volume=59| issue=4| pages=51–59|year=2005|doi=10.3130/jaabe.4.51|doi-access=free}}</ref><ref name="Smith2002">Smith, "[http://www.public.asu.edu/~mesmith9/1-CompleteSet/MES-02-EarlyCities.pdf Earliest Cities] {{Webarchive|url=https://web.archive.org/web/20100629224053/http://www.public.asu.edu/~mesmith9/1-CompleteSet/MES-02-EarlyCities.pdf |date=29 June 2010 }}", in Gmelch & Zenner (2002).</ref><ref>{{Cite journal |last=Danino |first=Matthew |year=2008 |title=New Insights into Harappan Town-Planning, Proportions and Units, with Special Reference to Dholavira |url=http://www.iisc.ernet.in/prasthu/pages/PP_data/paper2.pdf |journal=Man and Environment |volume=33 |issue=1 |pages=66–79 |archive-url=https://web.archive.org/web/20170525012828/http://www.iisc.ernet.in/prasthu/pages/PP_data/paper2.pdf |archive-date=2017-05-25}}</ref><ref>Jane McIntosh, ''The Ancient Indus Valley: New Perspectives''; ABC-CLIO, 2008; {{ISBN|978-1-57607-907-2}}  pp. [https://books.google.com/books?id=1AJO2A-CbccC&pg=PA231 231] {{Webarchive|url=https://web.archive.org/web/20200729144219/https://books.google.com/books?id=1AJO2A-CbccC&pg=PA231 |date=29 July 2020 }}, [https://books.google.com/books?id=1AJO2A-CbccC&pg=PA346 346] {{Webarchive|url=https://web.archive.org/web/20200729134430/https://books.google.com/books?id=1AJO2A-CbccC&pg=PA346 |date=29 July 2020 }}.</ref> The ancient Greek city of [[Priene]] exemplifies a grid plan with specialized districts used across the [[Hellenistic period|Hellenistic Mediterranean]].