Visitors take part in a tour in Son Doong cave, one of the world's largest natural caves, in central Vietnam's Quang Binh province, Jan. 19, 2021. (Photo/Agencies)
Stretching more than five kilometers long and reaching heights of 200 meters, the main cavern of Hang Son Doong is large enough to house an entire New York City block.
Photo shows a visitor taking part in a tour in Son Doong cave, one of the world's largest natural caves, in central Vietnam's Quang Binh province, Jan. 19, 2021. (Photo/Agencies)
Visitors climb down during a tour in Son Doong cave, one of the world's largest natural caves, in central Vietnam's Quang Binh province, Jan. 19, 2021. (Photo/Agencies)
