Son Doong Cave
Son Doong Cave holds the distinction of being the largest cave in the world. Discovered by Ho Khanh, a native of Phong Nha, in 1990, it underwent survey and measurement by an English-Vietnamese cave exploration group in 2009. Subsequently, in 2013, Son Doong earned recognition from the Guinness World Records as the world's largest natural cave.
With a total length of nearly 9 kilometers and a vast cave arch, Son Doong Cave boasts a volume of 38.5 million cubic meters. Within its chambers, visitors encounter towering stalactites, some exceeding 80 meters in height, alongside a primeval forest, unique ecosystem, and an underground river.
Offered as an adventure tourism experience, Son Doong cave exploration tours span 6 days and 5 nights, with bookings available since 2013. Demand for these tours remains consistently high, often fully booked a year in advance. This photo captures the Dinosaur Echo at Sinkhole 1 within Son Doong Cave.
Photo courtesy of Oxalis