Programs pursued as a means of improving the urban environment and achieving certain social and economic objectives. Evidence of urban planning can be found in the ruins of ancient cities, including orderly street systems and conduits for water and sewage. During the Renaissance, European city areas were consciously planned to achieve circulation of the populace and provide fortification against invasion. Such concepts were exported to the New World, where William Penn, in founding the city of Philadelphia, developed the standard gridiron plan—the laying out of streets and plots of land adaptable to rapid change in land use. Modern urban planning and redevelopment arose in response to the disorder and squalor of the slums created by the Industrial Revolution. The urban planner best known for his transformation of Paris was Georges-Eugène Haussmann. City planners imposed regulatory laws establishing standards for housing, sanitation, water supply, sewage, and public health conditions, and introduced parks and playgrounds into congested city neighbourhoods. In the 20th century, zoning—the regulation of building activity according to use and location—came to be a key tool for city planners. Seealso Pierre-Charles L'Enfant.
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Any set of climatic conditions that prevails in a large metropolitan area and that differs from the climate of its rural surroundings. Urban climates are distinguished from those of less built-up areas by differences of air temperature, humidity, wind speed and direction, and amount of precipitation. These differences are attributable in large part to the altering of the natural terrain through the construction of artificial structures and surfaces. For example, tall buildings, paved streets, and parking lots affect wind flow, precipitation runoff, and the local energy balance.
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(born 1318, Naples—died Oct. 15, 1389, Rome) Pope (1378–89). Archbishop of Acerenza (1363) and Bari (1377), he became papal chancellor for Gregory XI, whom he was chosen to succeed. This election of an Italian appeased the Romans, who wanted to end the French-dominated Avignon papacy, but his harsh reforms soon angered the French cardinals, prompting them to elect the antipope Clement VII, beginning the Western Schism (1378). Europe was divided in its loyalties, and Urban warred with Naples when its queen backed Clement. Strife over the schism reduced the Papal States to anarchy, and Urban's death may have been from poisoning.
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(born circa 1035, Châtillon-sur-Marne, or Lagery, or Lagny, Champagne, France—died July 29, 1099, Rome) Pope (1088–99). The prior of a Cluniac monastery, he was made cardinal by Pope Gregory VII, whose reforms he furthered. Elected pope in 1088, Urban secured his authority against the antipope Clement III and strengthened the role of the papacy in the reform movement. He called for the First Crusade at the Council of Clermont (1095) in response to the appeal of Alexius I Comnenus, promoted the union of the Eastern and Western churches, and supported the Christian reconquest of Spain from the Moors.
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Urban means "related to cities." It may refer to: