Don't look down! Vietnam launched a new attraction for tourists with a head for heights on Friday, with the opening of a glass-bottomed bridge suspended 150 metres (490 feet) above a lush jungle.

The Bach Long pedestrian bridge -- whose name translates to "white dragon" -- in northwest Son La province snakes around dizzying cliff faces before spanning a dramatic valley between two peaks, hitting a total length of 632 metres (690 yards).

The floor of the bridge is made from French-produced tempered glass, making it strong enough to support up to 450 people at a time, while giving them a spectacular view of the greenery in the gorge far below.

"When standing on the bridge, travellers will be able to admire the beauty of nature," Hoang Manh Duy, a representative of the bridge's operator said.

The company says it is the world's longest glass-bottomed bridge, surpassing a 526-metre structure in Guangdong, China.

Officials from Guinness World Records are expected to verify the claim next month.

Vietnamese tourism chiefs are seeking to lure visitors back after two years of Covid-19 shutdowns that kept out virtually all foreign travellers.

In mid-March, the country ended quarantine for international visitors and resumed 15 days of visa-free travel for citizens from 13 countries.

Vietnam is set to host the Southeast Asian Games in two weeks -- with more than 10,000 athletes and sports staff from countries in the region en route.

Bach Long is Vietnam's third glass bridge.

"I hope the bridge will lure more domestic and international tourists to our area," local resident Bui Van Thach said after walking across it.