Vietnam province reports robust tourism growth thanks to world's largest cave   Sunshine through a section of Son Doong Cave at around noon. The tour to the world's largest cave, offered by Oxalis, is opened for 500 tourists each year and tickets have been fully booked for 2016. Photo credit: Ryan Deboodt Quang Binh Province in central Vietnam has reported a remarkable 90 percent increase in tourism revenues this year thanks to successful promotions of its largest cave in the world. The province government said at a meeting this week that its tourism revenues has surged to VND179 billion (more than US$8 million), thanks to 3.9 increase in tourist arrivals, including a 9 percent increase in the number of foreign visitors to 46,900. It said the successful figures result from promotion efforts of the world’s largest cave Son Doong inside the province’s Phong Nha-Ke Bang cave system, especially after it appeared in the popular American talk show Good Morning America last May. The program was aired live from En cave, a feeder to Son Doong, as technical requirements did not the team to go deeper, after they had explored Son Doong earlier for footage, bringing more than one ton of specialized equipment, and ABC’s MC Zinger Zee called the cave Avatar. It was the first live feed from the Southeast Asian country for Good Morning America, the number one morning show in the US. Son Doong, or Mountain River, stretches for around five kilometers with at least 150 individual grottoes, shimmering rivers running through them, a dense subterranean jungle that keeps growing thanks to shafts of sunlight through the fallen stretches of the cave ceiling, and fossilized corridors, which prove there was life inside millions of years ago. Local man Ho Khanh discovered the cave in 1991, and in 2009 he helped British cave experts explore it. A tourist explores a platform inside Son Doong. Photo credit: Ryan Deboodt/Oxalis The cave has been praised as one of the most surreal places on earth. US magazine Smithsonian even named the cave the greatest place to see in the 21st century. Son Doong was first opened to tourists on a trial basis in August 2013. The local tour operator Oxalis which is the only one providing tourism services at Son Doong is charging tourists US$3,000 each for a one-week tour. The tour is opened for 500 tourists each year and tickets have been fully booked for next year. Quang Binh this year has opened more caves in and around the nature reserve to tourists, including Tu Lan, Tien, Va and Nuoc Nut, all of which have amazed tourists with their captivating limestone structures and primeval sight. Thanh Nien News