Do I need a passport and visa to go to Sanya?

No need. If you need to go abroad or go to Taiwan Province Province, Hongkong and Macau, you need a visa and passport.

Passport is a legal document issued by a country to prove the nationality and identity of its citizens when they enter and leave the country and travel or stay abroad. The word Passport means port pass in English. In other words, a passport is a passport for citizens to pass through international ports in various countries. Therefore, some countries in the world usually issue passes instead of passports.

Visa is the annotation and seal of the sovereign organ of a country on the passport or other travel documents held by its own or foreign citizens to show that they are allowed to enter or leave its own territory or pass through it. It can also be said that it is an endorsement certificate issued to them.

Generally speaking, a visa is a document issued by a country's entry-exit administration (such as immigration bureau or its embassy or consulate abroad) to approve the entry of foreign citizens.