Babylon, located in ancient Mesopotamia, is widely regarded as the first major urban center, dating back to around 2000 BCE.

Technological advancements, such as the steam engine and mechanized production, led to increased productivity and urbanization during the Industrial Revolution.

Athens, Greece, is often referred to as the 'Cradle of Western Civilization' due to its significant contributions to philosophy, democracy, and the arts.

Urbanization refers to the process of population shift from rural to urban areas, resulting in the growth of cities.

London was the first city to reach a population of one million, achieving this milestone in the early 19th century.

Urban sprawl refers to the uncontrolled expansion of urban areas into surrounding rural areas, often characterized by low-density development.

Rome, Italy, is often referred to as the 'Eternal City' due to its long and rich history, spanning over several millennia.

The decline of ancient Roman cities was primarily caused by barbarian invasions, which led to political and economic instability.

Angkor, Cambodia, is known as the 'City of a Thousand Temples' due to the numerous temples and religious structures located within its ancient ruins.

Urban renewal refers to the process of renovating and revitalizing older urban areas, often involving the demolition of existing structures and the construction of new buildings.

New York City, United States, is often referred to as the 'Big Apple' due to its vibrant cultural scene, diverse population, and economic significance.

Exurbanization refers to the movement of people from urban to rural areas, often characterized by the development of low-density residential areas beyond the suburbs.

Los Angeles, United States, is often referred to as the 'City of Angels' due to its association with the film industry and its sunny climate.

Gentrification refers to the process of replacing older buildings and structures with new ones in an urban area, often leading to an increase in property values and the displacement of low-income residents.

Hong Kong is often referred to as the 'Pearl of the Orient' due to its stunning natural scenery, vibrant culture, and economic prosperity.