World Travel City Photography

In the ancient Americas, early urban traditions developed in Mesoamerica and the Andes. Mesoamerica saw the rise of early urbanism in several cultural regions, including the Preclassic Maya, the Zapotec of Oaxaca, and Teotihuacan in central Mexico. Later cultures such as the Aztec drew on these earlier urban traditions. In the Andes, the first urban centers developed in the Chavin and Moche cultures, followed by major cities in the Huari, Chimu and Inca cultures.
This roster of early urban traditions is notable for its diversity. Excavations at early urban sites show that some cities were sparsely populated political capitals, others were trade centers, and still other cities had a primarily religious focus. Some cities had large dense populations, whereas others carried out urban activities in the realms of politics or religion without having large associated populations. Theories that attempt to explain ancient urbanism by a single factor, such as economic benefit, fail to capture the range of variation documented by archaeologists (Smith 2002).
The growth of the population of ancient civilizations, the formation of ancient empires concentrating political power, and the growth in commerce and manufacturing led to ever greater capital cities and centres of commerce and industry, with Alexandria, Antioch and Seleucia of the Hellenistic civilization, Pataliputra (now Patna) in India, Chang'an (now Xi'an) in China, Carthage, ancient Rome, its eastern successor Constantinople (later Istanbul), and successive Chinese, Indian and Muslim capitals approaching or exceeding the half-million population level.
Keith Hopkins estimates that ancient Rome had a population of about a million people by the end of the 1st century BC, after growing continually during the 3rd, 2nd, and 1st centuries BC. Alexandria's population was also close to Rome's population at around the same time, the historian Rostovtzeff estimates a total population close to a million based on a census dated from 32 AD that counted 180,000 adult male citizens in Alexandria. Similar administrative, commercial, industrial and ceremonial centres emerged in other areas, most notably medieval Baghdad, which according to George Modelski, later became the first city to exceed a population of one million by the 8th century instead of Rome.