The largest province of the South, Surat Thani was once a provincial capital of the 10th century Indonesian Srivijaya Empire, and now covers an area of approximately 13,000 square kilometers of both low basins and high plateaus with forested mountains, as well as some of Thailand’s most famous islands including Koh Samui, Koh Phangan, Koh Tao, and the Mu Koh Ang Thong Marine National Park.