Phuket Once in a lifetime you have to visit Phuket, the largest island in Thailand and most popular destination after Bangkok. Phuket is Thailand’s largest island, approximately the size of Singapore. Lying 862 kms. south of Bangkok, Phuket is nestled in the balmy waters of Andaman Sea, Thailand’s portion of the Indian Ocean. Phuket is blessed with magnificent coves and bays, palm-fringed powdery white beaches and sparkling island-dotted seas.