The question: what is the biggest city in the world is actually not as simple as it first appears. Just as there is often more than one way to accomplish a task, there is more than one to define how large a city is.
Cities are judged by size based on several criteria and the results are often rather controversial due to bias and data manipulation by those who seek to portray “their” city in the best possible light. How large a city is depends on how a city is defined, which is open to debate. Generally speaking, the size of a city is normally judged on two main criteria: land area and population, but other criteria can also be used.
Morphological refers to the size of the city’s contiguous urban area without taking into account any territorial boundaries. Strict guidelines are used, including distances between buildings and density of structures. Satellite photographs are a useful way of judging this.
Functional defines a city by its demographic population. This assesses the metropolitan area of the city based on commuting between home and work.
Administrative defines the area of a city based on municipality or government. It can also include more than one municipality under the umbrella of one regional government.
The biggest city in the world by size of its urban area without regard for administrative boundaries is Tokyo, Japan. The city is the capital of Japan and as well as being the biggest metropolitan area in Japan, it is also home to more than 8 million people, including the Japanese Imperial Family, which also makes it the biggest city in the world by population.
Tokyo is one of the world’s three major cities for the financial markets and is a vast, sprawling metropolis that encompasses dozens of smaller cities, districts, towns, villages, and a national park. The city of Tokyo has three distinct municipal wards, each governed separately, but under the overall control of a central governor.
The biggest city in the world by population is Shanghai in the People’s Republic of China. Shanghai is the most densely populated urban areas on the planet. The city is located on the mouth of the Yangtze River and is also the world’s largest cargo port.
Shanghai first opened up to the west in 1842 and since then it has become a vital centre of international trade between the east and west. The city is considered a “showpiece” for China after it was extensively rebuilt following widespread bombing World War II and it is an important business and financial hub in the world economy.
It is also a popular tourist destination as it contains a number of historical landmarks including the City God Temple and the Bund. Today, the Shanghai skyline is almost as well known as the New York City skyline and the famous Oriental Pearl Tower is probably as much photographed as the Empire State Building.
Both Tokyo and Shanghai are well worth a visit if only admire the sheer magnitude of these vast urban megalopolises.