About Phong Nha National Park
The World Heritage-listed Phong Nha-Ke Bang national park covers an area of 860km² of limestone forest along the Lao border and includes about 300 caves. The most famous of these caves, the Phong Nha cave, was used as an ammunition depot and hospital by the North Vietnamese during the war and lied close to the Ho Chi Minh Trail. The cave is now accessible by boat, which can travel 1.5km up river to explore the cave’s impressive formations. In 2009, British cavers discovered the world’s largest cave inside the national park – the Son Doong cave runs for 5km, is 200m high and 150km wide.