It is a natural phenomenon where hundreds and thousands of holes have been worn away in the ground’s surface by the water of the mighty Mekong River. During the dry season you can walk along the dry edges of the river and see this awesome sight. Some holes are small and some are huge, some are dry and others are filled with water – you can clamber down into some of the large dry holes and have a picture taken where you look so tiny in the gaping opening!