The world’s population keeps rising and is expected to peak at around 10.4 billion in 2100, according to the United Nations. More than half of people already live in cities, and that figure is expected to reach almost 70% by 2050.
Some cities have grown so large they are now classed as “mega-cities” with more than 10 million residents. Based on population data from the World Population Review, the biggest city on Earth has 37 million people, more than London (9.8 million), New York (7.9 million) and Paris (11.3 million) combined.
Here are the 7 biggest mega-cities in the world:
Tokyo, Japan - 37 million people
Tokyo is the largest city in the world. Its metro area has just over 37 million people. The city is known for its reliable trains, busy streets and huge shopping districts.
Popular places for visitors include Shibuya Crossing, Senso-ji Temple and the city’s many parks and gardens. While the population has started to decline slightly, it remains the biggest city in the world by far.
(Image: Getty)Delhi, India - 34.67 million people
Delhi has nearly 35 million residents. The city is home to historic landmarks such as the Red Fort and India Gate, as well as large markets and busy roads.
Its rapid growth has put pressure on housing, transport and air quality. Visitors often explore its temples, museums and street food stalls.
(Image: Getty)Shanghai, China - 30.48 million people
Shanghai is home to just over 30 million people. It's has the world’s busiest container port and a skyline that includes the Oriental Pearl Tower and Shanghai Tower.
Popular areas for visitors include the Bund, Yu Garden and Nanjing Road. The city has grown quickly in the past few decades.
(Image: Getty)Dhaka, Bangladesh - 24.65 million people
Dhaka has almost 25 million people living in a small area, making it one of the most crowded cities on Earth. Many people have moved there from rural areas in search of work.
The city is known for its colourful rickshaws, mosques and lively street markets. It faces problems with traffic, flooding and limited space.
(Image: Getty)Cairo, Egypt - 23 million people
Greater Cairo is the largest city in Africa and the Middle East with over 22 million people. The city is close to the Pyramids of Giza and the Sphinx, which attract millions of tourists each year.
Its streets are busy with markets, shops and street food stalls. Rapid population growth has created challenges for housing and transport.
(Image: Getty)São Paulo, Brazil – 22.99 million people
São Paulo is the biggest city in South America with almost 23 million residents in its metro area. It is known for its tall buildings, wide roads and large shopping areas.
Football is a massive part of life in the city, with several big stadiums hosting matches. Public transport is widely used, though traffic jams are still common.
(Image: Getty)Mexico City, Mexico - 22.75 million people
Mexico City is the largest Spanish-speaking city in the world with around 22.75 million residents. It is home to historic attractions such as the Zócalo and the ancient ruins of Templo Mayor.
The city also has large parks and busy food markets. In recent years, heavy rainfall and flooding have affected some neighbourhoods.
(Image: Getty)