Tales of lost cities, submerged ancient ruins, and peculiar creatures abound beneath the calm, murky surface of many lakes. Tagaytay’s lakes are no exception. Back in prehistoric times, the area of Tagaytay, including the surrounding provinces of Cavite and Batangas, were all part of a massive volcano estimated to be 18,000 feet high. An eruption caused its collapse into the complex’s 20x30 km Taal caldera, one of the great volcano-tectonic depressions of the world, with a channel opening towards Balayan Bay. 

            This channel between the sea and what is now known as Lake Taal was traced in maps and documents from the 1500s to the 1700s. Along its shores, numerous towns mushroomed. In 1572, Taal Volcano erupted again, burying the nearby towns in ash, lava, and mud laced with sulfuric acid, which chemically burned victims to death. In 1754, Taal Volcano decided to give its environs a geographic makeover. The eruption that year, which early Augustinian priests reported as having lasted up to six months, pulverized all the towns along the shores, sealed the open channel to the sea, and surrounded the volcano with its own sea-water lake. That same year, the monsoon season filled Lake Taal up to 10 meters, effectively turning it into fresh water. Between 1572 to the present, Taal Volcano erupted more than 41 times.

Just Below the Surface
            Thomas Hargrove, author of The Mysteries of Taal: A Philippine Volcano and Lake, Her Sea Life and Lost Towns, conducted around seventy dives into Taal Lake for his book, revealing exactly what lies beneath her placid surface. First, the lake has a uniform depth of about 30 feet all around it, and on its muddy floor rests an ancient beach littered with seashells. Second, because of its salt water origins, Taal Lake is home to the only known species of a venomous black and white sea snake that breeds in fresh water, Hydrophis semperi .