The crater lake of Mt. Pinatubo on the island of Luzon is without doubt one of the natural wonders of the Philippines. It was formed in 1991 when the great volcano famously erupted, disrupting the worldwide climate for over two years. Small in surface area, it's the deepest lake in the country at about 600 meters (2k ft.) maximum depth. In this video, you'll get a fabulous drone's eye view of the great lake, compliments of contributor url_eleven. There are continued fears that the crater walls could suffer a catastrophic break at some point.