The caves have a total length of 11.7km. Of the new discovers, 20 were found in Lam Hoa commune of Tuyen Hoa district, as well as in Hoa Phu and Hoa Son communes of Minh Hoa district, while the rest are inside Phong Nha-Ke Bang National Park. The search for the new caves involved explorers from the UK, Australia, and New Zealand who had worked for three weeks with support of tour guides and a number of locals. In order to exploit the caves for tourism and exploration activities, the British Cave Research Association recommends that Quang Binh conduct further researches to evaluate their safety, ceiling heights, flow, and geomorphology of the caves. With about 500 caves discovered, Quang Binh is renowned as the country's kingdom of caves. There are over 40 caves in the locality which are open to tourists. Son Doong is the world's largest, while En and Pigmy come in at second and fourth./.