Haikou is the core city of Hainan and the administrative center of the capital city of Hainan. Facing the sea, the seasons are like spring. Its air quality ranks first among 74 key cities in China for six consecutive years, and it is one of the most livable cities in China. Haikou is known as one of the top ten cities, a national environmental protection model city, a national health city, an excellent tourist city in China, a national garden city and a national historical city. Haikou is the only city in Hainan Province that has both big city facilities and scarce landscape. Who announced the air quality ranking of 1 100 cities in the world, and Haikou ranked first in the country; Haikou has 365 days a year, and the days with excellent air quality are 3 1 1 day.

Second, Chengmai

Chengmai County has attracted worldwide attention for its natural ecological environment, beautiful natural landscape, warm climatic conditions, special selenium-enriched food, long historical and cultural landscape, ancient volcanic villages and rapid social and economic development. Chengmai County has won more than 60 national awards, such as "Hometown of Longevity in the World", "Green Famous County in China", "Best Leisure Tourism County in China", "Demonstration County in beautiful countryside, China" and "Top Ten Famous Tourism Counties with Cultural Characteristics".

Third, Sanya.

Sanya is a prefecture-level city under the jurisdiction of Hainan Province, also known as Lucheng. Sanya, located at the southernmost tip of Hainan Island, is an international tourist city with tropical coastal scenery [1], a coastal city in China and one of the best cities in China. Sanya is also called "Oriental Hawaii". Sanya faces the South China Sea, and there are many bays, each with its own beautiful scenery.

Fourth, Lingshui

Lingshui county is rich in natural resources, especially mineral resources, agriculture, tourism and marine resources. The climate belongs to tropical island monsoon climate, with high temperature all year round, distinct dry and wet seasons, rainy summer and autumn, and dry winter and spring. The annual average temperature is 25.2℃, and the annual average rainfall is 1500 ~ 2500mm, mainly in August ~ 10 every year. With abundant sunshine, frost-free all year round and evergreen seasons, it is a rare natural greenhouse in China.