isthmus of kra
narrow neck of southern Myanmar (Burma) and Thailand, connecting the Malay Peninsula to the Asian mainland. The isthmus lies between the Gulf of Thailand to the east and the Andaman Sea to the west. It is 25-30 miles (40-48 km) wide at its narrowest point, between Chumphon and Kra Buri (both in Thailand). Kra Buri, for which it was named, is at the head of the Pakchan River estuary, an inlet of the Andaman Sea.
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