A Train Runs on the Eastern Ring in Haikou, Dec 24, 2015.

The 345-km west loop high-speed railway was officially put into operation on Wednesday. It has 16 stops in six cities and counties, linking provincial capital Haikou with Sanya, a tropical tourist spot. It began construction in Sept 2013 with an investment of 27 billion yuan ($4.23 billion).

The 308-km eastern ring, also from Haikou to Sanya, was put into operation at the end of 2010 with a designed speed of up to 250 km per hour. It passes Boao, a scenic town where the Boao Forum for Asia is held annually.

With a land area of 35,400 square km, Hainan is slightly larger than Belgium. A popular destination for beach lovers, it is expected to receive 47 million visitors this year.