Ha Long Bay, Vietnam

Ha Long Bay is a UNESCO World Heritage Site, and a popular travel destination, in Quảng Ninh Province, Vietnam. Administratively, the bay belongs to Hạ Long City, Cẩm Phả town, and part of Vân Đồn District. The bay features thousands of limestone karsts and isles in various sizes and shapes. Hạ Long Bay has an area of around 1,553 km2, including 1,960–2,000 islets, most of which are limestone. The limestone in this bay has gone through 500 million years of formation in different conditions and environments.