Son Doong, The world´s biggest cave is in Vietnam The world´s biggest cave is the Son Doong cave in the national park Phong Nha-Kẻ Bàng. It is in a way at the same time an ancient cave and a new discovery, only ca. 12 years since this miracle of nature was found. The Son Doong … Continue reading Son Doong in Vietnam is the world´s biggest cave by far.