Tourists explore the narrow and dark caves of Tràng An Scenic Landscape Complex near Ninh Binh, a World Heritage site in Vietnam.
In the claustrophobic footage, a woman is seen navigating her tour boat through the cave, using only two paddles and squeezing through small gaps in the rock.
Filmed in January 2020, the tour takes around two hours and opens out into an area of spectacular natural beauty.
