Taal Lake is a freshwater lake in the province of Batangas, on the island of Luzon in the Philippines. It is the country's third largest lake after Laguna de Bay and Lake Lanao. Volcano Island, the location of Taal Volcano's historical eruptions and responsible for the lake's sulfuric content, lies near the center of the lake. There is a crater lake on Volcano Island, which is the world's largest lake on an island in a lake on an island. Known as the Main Crater Lake, it contains its own small island, Vulcan Point.