Bulusan, Mount

Bulusan, Mount,

active stratovolcano, Sorsogon prov., S Luzon Island, Philippines, rising to 5,133 ft (1,565 m). Bounded on the W and S by other volcanic mountains, it is near the southern end of the Bicol peninsula and occupies the northeastern portion of the Irosin caldera, which was formed by an eruption some 36,000–40,000 years ago. Bulusan has four craters and four springs and is one of the most active volcanoes in the Philippines, with steam-generated "phreatic" eruptions that often occur without warning. The volcano is surrounded by Mount Bulusan Volcano National Park, 9,080 acres (3,673 hectares), which includes rainforest and Bulusan Lake.