Beijing is also known as Peking and is the capital of China’s People’s Republic of China. It is home to more than 21 million people and occupies an area of 16,410.5 kilometres (6336 sq. mi. ).
It is located in Northern China. It is administered as a municipality by the State Council. 16 districts include urban, suburban and rural areas. Hebei Province surrounds Beijing, except Tianjin to its southeast. Together these three divisions make up the Jingjinji megalopolis and the nation’s capital region.

Shanghai is one of the four Chinese municipalities directly administered by the People’s Republic of China. It is situated on the Yangtze River’s southern estuary, where the Huangpu River flows through it. As of 2020, the city has a population of 24.87 million.
China’s most populous urban area and East Asia’s largest city. Shanghai is a major global financial, business, and economic centre. It also hosts research, education and science. Shanghai’s Port is the busiest container port in the world.

Shenzhen, also known as Sham Chun, is a major sub-provincial city and one of the special economic zones of China. 

The city is located on the east bank of the Pearl River estuary on the central coast of southern province of Guangdong, bordering Hong Kong to the south, Dongguan to the north, and Huizhou to the northeast. With a population of 17.56 million as of 2020, Shenzhen is the fourth most populous city proper in China. Shenzhen is a global center in technology, research, manufacturing, finance, and transportation, and the Port of Shenzhen is the world’s fourth busiest container port.

Guangzhou, also known as Canton and alternatively romanized as Kwongchow or Kwangchow, is the capital and the largest city of Guangdong province in southern China. Located on the Pearl River about 120 km (75 mi) north-northwest of Hong Kong and 145 km (90 mi) north of Macau, Guangzhou has a history of over 2,200 years and was a major terminus of the maritime Silk Road, and continues to serve as a major port and transportation hub, as well as one of China’s three largest cities. 

Chongqing, also called Chungking in some parts of China, is a city in southwest China.
It is one of four municipalities that fall under the direct supervision of the central government of China. It is also the only municipality of this type located deep in the interior. Chongqing’s municipality is approximately the size of Austria. It includes Chongqing and several other dispersed cities. Chongqing municipality is the largest city but does not have a large urban area. This is due to a classification technicality.