HA LONG BAY EXPLORED
How this stunning Vietnamese bay developed such distinctive geology
WORDS AILSA HARVEY
Did you Know
Ha Long Bay had 4.4 million visitors in 2019
The islands and rock formations vary widely in size
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In the Gulf of Tonkin, 101 miles southeast of Hanoi, Vietnam, around 2,000 chalky pillars and islands protrude from the sea. These towering limestone rocks are called karsts, and they’ve been sculpted into unique shapes by erosion from the rain and sea. Most of them are between 50 and 100 metres tall. The geological evolution that led to this seascape was a 500-million-year process, with the limestone beginning to form about 300 million years ago.