The Gulf of Thailand (Thai: อ่าวไทย, RTGS: Ao Thai, Thai pronunciation: [ʔàːw tʰaj]), also known to Malays as Teluk Siam, literally meaning Gulf of Siam, and Boeung Tonle Siem in Khmer, is a shallow arm of the South China Sea.
Ko Samui (or Koh Samui, Thai: เกาะสมุย, Thai pronunciation: [kɔ̀ʔ samǔj]), or often simply Samui as it is referred to by locals, is an island off the east coast of the Kra Isthmus in Thailand. It is located close to the mainland town of Surat Thani in Surat Thani Province. It is Thailand's third largest island after Phuket and Ko Chang, with an area of 228.7 km2 and a population of over 62,000 attracting 1.5 million tourists per year. Ko Samui has abundant natural resources, white sandy beaches, coral reefs and coconut trees. It is part of Mu Ko Samui.