Speed, distance limits imposed on vessels near Ha Long Bay's iconic islets

Experts said their underside has eroded and they have developed cracks.

The Quang Ninh Province Department of Transport said Tuesday vessels have to keep below 10 kph and at least 70 m away when passing by the islets.

Buoys have been placed so that vessels know the appropriate distance, it added.

In July a report by the Vietnam Institute of Geosciences and Mineral Resources said the islets were being impacted by several natural factors, which could cause them to collapse into the sea.

Even if no tourist is allowed to set foot on the islets, vessels passing by could impact them, it warned.

Boats carrying four or more people and traveling at 30 kph could create waves 40-60 cm high, while larger vessels could create waves over 80 cm high, which would have a severe effect on the islets, it said.

Over time they would hasten their erosion, it added.

Researchers also called for using anchors and cement to slow down the erosion and prevent blocks of rocks from falling off.

Ha Long Bay lost the Thien Nga islets in 2016 when a part of it collapsed. In Kien Giang, the Phu Tu islets, deemed a "National landscape" in 1989, partially collapsed in 2006.

Trong Mai, located some seven kilometers from the Ha Long international tourism port, has two small islets around 12 m tall that resemble a rooster and hen.

It is considered one of the tourism symbols of Ha Long Bay, and in 2000 was in fact chosen as Vietnam's tourism symbol.