<P> Almost all these islands are as individual towers in a classic fenglin landscape with heights from 50m to 100m, and height / width ratios of up to about six . </P> <P> Another specific feature of Ha Long Bay is the abundance of lakes inside the limestone islands . For example, Dau Be island has six enclosed lakes . All these island lakes occupy drowned dolines within fengcong karst . </P> <P> Ha Long Bay is located in northeastern Vietnam, from E106 ° 55' to E107 ° 37' and from N20 ° 43' to N21 ° 09' . The bay stretches from Yen Hung district, past Ha Long city, Cam Pha town to Van Don District, bordered on the south and southeast by Lan Ha Bay, on the north by Ha Long city, and on the west by Bai Tu Long Bay . The bay has a 120 km long coastline and is approximately 1,553 km2 in size with about 2,000 islets . The area designated by UNESCO as the World Natural Heritage Site incorporates 434 km2 with 775 islets, of which the core zone is delimited by 69 points: Dau Go island on the west, Ba Ham lake on the south and Cong Tay island on the east . The protected area is from the Cái Dăm petrol store to Quang Hanh commune, Cam Pha town and the surrounding zone . </P> <P> The climate of the bay is tropical, wet, sea islands, with two seasons: hot and moist summer, and dry and cold winter . The average temperature is from 15 ° C - 25 ° C, and annual rainfall is between 2 meters and 2.2 meters . Ha Long Bay has the typical diurnal tide system (tide amplitude ranges from 3.5 - 4m). The salinity is from 31 to 34.5 MT in the dry season and lower in the rainy season . </P>

Is halong bay in north or south vietnam
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