Chonburi (Thai: ชลบุรี, RTGS: Chon Buri, [tɕ͡ʰōn bū.rīː] ( listen)) is an eastern province (changwat) of Thailand. Neighboring provinces are (from north clockwise) Chachoengsao, Chanthaburi, and Rayong. To the west is the Gulf of Thailand. Chonburi is home to Thailand's largest tourist oriented city, Pattaya (also spelled Phatthaya), it is the only province outside the Bangkok Metropolitan Area to connect by an eight-lane motorway to Bangkok, 80 km distant. It is home to Thailand's largest and primary seaport, it has a thriving migrant and expatriate population. Due to these factors, the province's population is growing rapidly, with currently some 1.7 million residents (albeit with a large floating or unregistered population). The registered population as of 31 December 2012 was 1.36 million.