Southern Thailand includes many of Thailand‘s most famous resorts on both the west-facing Andaman Sea coastline, and the east-facing Gulf of Thailand coast south of Chumphon.
Southern Thailand is on the Malay Peninsula, bounded to the north by Kra Isthmus, the narrowest part of the peninsula. The western part has highly steep coasts, while on the east side river plains dominate. The largest river of the south is the Tapi in Surat Thani, which together with the Phum Duang in Surat Thani drains more than 8,000 km2, more than 10 percent of the total area of southern Thailand. Smaller rivers include the Pattani, Saiburi, Krabi, and the Trang. The biggest lake of the south is Songkhla Lake (1,040 km2 altogether). The largest artificial lake is the Chiao Lan (Ratchaprapha Dam), occupying 165 km2 of Khao Sok National Park in Surat Thani.
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