By air. Sanya Phoenix International Airport (SYX) sits about 40 km west of Yalong Bay, with multiple daily flights from Beijing, Shanghai, Guangzhou, and Hong Kong, plus a thinner international schedule from Seoul, Singapore, and Bangkok. A taxi to Yalong Bay costs around RMB 150 and takes 45 minutes; most resort hotels run shuttles for arriving guests.
By high-speed rail. Sanya Station, in the centre of Sanya city, is the southern terminus of the Hainan high-speed rail loop. From Haikou (the provincial capital, at the northern end of the island) the trip takes about 90 minutes. From the station, taxis run to Yalong Bay in about 30 minutes.
Local bus. Sanya bus 15 runs between Sanya city and Yalong Bay, with stops along the bay road. RMB 5; takes about an hour. Useful for day trips but slow if you have luggage.