Haikou is the capital and most populous city of Hainan province. Administratively, Haikou is a prefecture-level city, including four districts, and covering 2,280 square kilometers (880 sq mi). There are 2,046,189 residents in the built-up area all living within the 4 urban districts of the city. Haikou was originally a port city. Today, more than half of the island's total trade still goes through its ports.
Many streets in Haikou are quite different during the day compared to the evening. Small outdoor restaurants and stalls fill the streets in the evening and many areas are at their busiest from 9.00 pm to 1.00 am. Local favorites are BBQ stalls that serve cheap local beer till late. You will soon notice the abundance of coconut trees in Haikou. It is greener than most Chinese cities and the city has decent air quality. Hainan, with its varying climatic zones, is home to a huge diversity of wildlife predominantly found in the rain forests.
Haikou is linked to Sanya and other cities of the island by an expressway. The city's international airport has flights to other major cities in China, as well as to Thailand, Singapore, and other Southeast Asian countries. Food processing and the manufacture of rubber goods, electronics, and machinery are the major industries of Haikou.