IntroductionAn emerging problem is that of urban expansion. Although some aspects of urban sprawl have been observed since ancient times, this phenomenon began to gain greater momentum in the last century, aided by the advancement of technology, particularly with the increased production of automobiles, homes, and highway systems. Many people contribute unknowingly to this environmental problem, as is its nature. Urban sprawl concerns the growth of the suburbs, the area between the urban and rural areas of a city. Most of America's largest cities and states, in terms of population, are prime examples of urban sprawl. Opponents of urban sprawl usually cite the government as a major cause of urban sprawl. Government may be a major catalyst for sprawl today, but the history of sprawl traces primarily back to an economic and social root rather than a political one. Ironically, urban sprawl is also known as rural sprawl; the terms simply refer to the spread of population and urban area into rural areas (Cornell University). With advancing human development comes the destruction of wilderness areas, which is commonly known to contribute to a wide variety of environmental problems. Cars are also a major part of sprawl, contributing to the depletion of global oil reserves and the release of greenhouse gases into the atmosphere. Noticing these negative effects, some communities across the country and world are taking steps to reduce the sprawl of their cities, ultimately saving the environment. History and Description of Urban Expansion The roots of the suburbs can be seen thousands of years ago in ancient Rome, where the city was incredibly crowded and dense within the city walls. Had the current population......center of the paper......areas of urban growth." NASA, nd Web. December 3, 2013. .Tachieva, Galina. "Sprawl Repair: From Sprawl to Complete Community, by Galina Tachieva: Articles: Terrain.org." Terrain.org. Np, nd Web. November 29, 2013. United States Congress. Compact Cities: Energy Saving Strategies for the 1980s. Washington: USGPO, 1980. Print. United States Environmental Protection Agency. Commercial Strip Redevelopment: A Practical Guide for Planning the Revitalization of Deteriorating Corridors by ICF International and Freedman Tung & Sasaki Washington, DC: U.S. Environmental Protection Agency, 2010. Pearland Independent School District , nd Web, 12 December. 2013. .