Evidence of urban planning has existed since ancient times. In ancient Greece the first settlements became cities and did not follow particular urban plans, with the exception of their acropolis. However, excessive population growth in these city-states led to the wave of colonization of the Mediterranean during what is known as classical antiquity. Colonies were founded by their metropolises after carefully selecting their locations, providing access to natural resources (minerals, fertile lands, water) and trade routes. These cities were usually designed following the Hippodamian plan of city layout. The Hippodamian plan was first introduced by Hippodamus of Miletus who rationalized the functions of the city, the underlying road network and the uses of the land. He proposed a city composed of three centers, one political, one commercial, and one religious, each providing specialized functions to the city's population. Not all plans lead to the successful growth of cities. Famous is the case of Megalopolis in the southwestern Peloponnese, which at the time was planned to become a megalopolis, as can be deduced from its name. Although a functioning road network laid the foundation for urban development and monumental public buildings, such as the largest known ancient theater, were constructed, the city failed to attract inhabitants and ended its life never becoming more than an insignificant suburban town. In Roman antiquity, urban plans systematically included the provision of clean water, thus leading to the creation of the Roman aqueducts that can still be seen throughout Europe today. During the Dark Ages in most of Western Europe city planning was reduced to plans for city fortifications, including...... half of paper ...... as they focused only on the aesthetics of a city . His book helped the progressive movement take shape. Progressives argued that planning should address all the major problems of American cities and proposed a system of zoning. In the beginning zoning focused on the size of buildings, however a more modern approach deals with land use, population and housing density, parks, thus leading to more complex zoning systems. (Fleissig and Jacobsen, 2002). In the modern era, zoning has played a crucial role in the flourishing of the urban planning profession. In many countries zoning must be justified by a rational plan and, if necessary, the outcome of the plan can be justified in court. Therefore qualified planners with experience are needed to carry out the task. The main zoning classes are industrial, residential and commercial, but these classes can be further refined.