A Multiple-Nuclei Model city is a city that does not have one central area, but instead has several nodes that act as regional centers for economic or residential activity within one larger city. Los Angeles, with its many distinct neighborhoods, is a prototypical example of this type of city.

Lagos is the capital city of Nigeria and is by far the most populous city in Africa. More than ten million people live within the city of Lagos, and an additional ten million live within the metropolitan area of Lagos. The next most populous cities in Africa are Cairo, in Egypt, and Kinshasa, in the Democratic Republic of Congo.

A “gateway city” is a city that serves as a port of entrance for migrants arriving in a country or a large geographic region. Cities like New York City, San Francisco, and Rio de Janeiro are classic examples of gateway cities.

In human geography the term “gateway city” refers to a city that acts as a port of entry into a country or a large geographic region. San Francisco with its natural harbor and immigrant population, often referred to as the “gateway to the west,” is a classic example of a gateway city.

Medina is a prominent city in Saudi Arabia and, with its mosques, open-air markets, and prominent courtyards. As such, Medina is a classic example of an “Islamic city” from religious, cultural, and aesthetic perspectives. Sofia is in Bulgaria; Venice is in Italy; Barcelona is in Spain; Tblisi is in Georgia.

London, Tokyo, and New York City are the only cities in the world that are considered to be first-tier world cities. This means they are global centers of culture, economics, and politics that have a disproportionately massive influence on the global population. Capital cities and economic centers like Moscow, Brussels, Mumbai, Los Angeles, and many others are considered to be “second-tier world cities.”

Many cities first began to take shape in the late Medieval period. These cities, common throughout Europe and parts of the rest of the world, are characterized by their narrow, winding streets and looming, intimate buildings. They generally have some defensive fortifications and cathedrals and ostentatious churches dotting the landscape.

A classic feature of a colonial Latin American city is that it has distinct segments divided up for residential, commercial, and industrial purposes. It typically has a central business district from which all other parts of the city radiate out.

Istanbul, the capital of Turkey and an ancient and significant city, is the most populous city in Europe. Istanbul actually lies at the boundary between Europe and Asia, but the city itself is considered European. There are more than fourteen million people living within the city limits of Istanbul, compared with twelve million in Moscow, 8.5 in London, 2 million in Paris, 3.1 million in Madrid, and 1.4 in Munich.

“Islamic cities” are considered as a distinct category of city within the study of human geography. Typically Islamic cities arose in places with warm climates and fairly little rainfall so they tend to be painted white (to reflect sunlight) and have facilities to recycle rainwater. They also typically contain vibrant open-air markets and picturesque mosques.