Vietnam grotto contains the system of grottoes and caves. They are mainly located in the north Vietnam.
Until 2000, only 200 grottoes being discovered with 90% is short and medium length. In 2003, more than 300 grottoes being discovered with many grottoes of more than 1000m length in the West North.
Until 2010, Quang Binh have discover 300 grottoes in Phong Nha-Ke Bang, Ninh Binh with over 100 grottoes in Trang An. That increase the number of grottoes to 1000... Read more >>