Baie D Along, Vietnam

Baie D Along, Vietnam is a vast bay natural water marine area of ​​more than 43,000 hectares (1,500 km 2 , the largest marine karst in the world located between Hạ Long and Cat Ba National Parkfrom the island of Cat Ba , in the Gulf of Tonkin of the South China Sea , from the province of Quảng Ninh in northern Vietnam , to the Chinese border of Dongnan Qiuling , 170 km east of the capital Hanoi . Its 120 km of coastline coastal , natural seascape spectacular and exceptional preserved 1969 islands karst limestone submerged, and wealth Biological its ecosystem tropicalworth it to be on the list of World Heritage of UNESCO since December 17 , 1994(with an extension in 2000 ).

This site of the most beautiful bays in the world , elected in 2011 one of the new seven wonders of nature , is one of the most important tourism destinations in Vietnam and tourism in the world with 2.5 million annual visitors in 2015.