Hong Kong geologists have revealed for the first time the full extent of an ancient supervolcano with a diameter of 18km sitting beneath the former British colony.
The giant ash monster is thought to be of the same collapse caldera type as the infamous Krakatau volcano which killed tens of thousands and literally rocked the world when it blasted open near the Indonesian islands of Java and Sumatra in 1883.
The discovery – one of only around 50 such volcanoes in the world – is a coup for the local rock boffins, who have been digging around the Geopark in Sai Kun in the east of the Special Administrative Region for several years.