Boosted by upgraded offshore duty-free shopping and the restart of interprovincial group tours, Sanya — located at the southern tip of tropical Hainan Island — is becoming a hot destination for family tours, parents with schoolchildren and older students who have just completed their national college entrance.

More than 90 percent of the rooms at hotels in Yalong Bay and Haitang Bay, two luxury clusters in Sanya, were booked by the latter half of July, said Deng Yongbo, secretary-general of the Sanya Tourism Federation.

"Most of the rooms in high-end hotels, such as the Atlantis Sanya resort, are filled for the first half of August.

The luxury hotels and high-end products have become favorites of tourists, who are spending money liberally, Deng said, adding that the quality of the overall market has improved.

With the duty-free shopping quota raised from 30,000 yuan ($4,308.95) to 100,000 yuan ($14,400) per person annually as of July 1, as part of the effort to boost the development of Hainan Free Trade Port, Hainan recorded tourist spending on offshore duty-free goods worth 2.22 billion yuan from July 1 to 27, up more than 234 percent from the same period last year, according to the General Administration of Customs.

Reports from big-data services show that the number of people searching for airline tickets has doubled and the number searching for hotel rooms in Sanya has tripled since Hainan's new offshore duty-free policy took effect.

Local officials said Sanya tourism companies have developed a rich list of family-tour packages with themes focusing on sea entertainment, surfing, yachting and visits to tropical rainforests, botanical parks, ocean parks and villages that provide immersive experiences with the culture of the Li people, the original inhabitants of Hainan.

More than 281,000 tourists visited the island during July, up almost 43 percent year-on-year, according to local tourism authorities.

"We enjoyed the package tours. My family explored and experienced the attractions of Hainan Island together. It was a joyful family reunion and we expect to come back," a tourist from Sichuan province said.