Volcano Pompeii. Before its catastrophic eruption of 1991, Pinatubo was an inconspicuous volcano, unknown to most people in the surrounding areas. Two other examples are the long-dormant Soufrière Hills volcano on the island of Montserrat, thought to be extinct before activity resumed in 1995, and Fourpeaked Mountain in Alaska, which, before its September 2006 eruption, had not erupted since before 8000 BCE and had long been thought to be extinct. The three common popular classifications of volcanoes can be subjective and some volcanoes thought to have been extinct have erupted again. To help prevent people from falsely believing they are not
Arenal Volcano National Park Arenal Volcano National Park Arenal Volcano National Park () is a Costa Rican national park in the central part of the country, forming the Arenal Tilaran Conservation Area. The park encompasses the Arenal Volcano, which "was" the most active in the country, which had previously been believed to be dormant until a major eruption in 1968. It neighbors Lake Arenal, which is the site of the country's largest hydroelectricity project, the Lake Arenal Dam. The park also contains a second volcano, Chato, whose crater contains a lagoon. It is also called Cerro Chato (literally Mount Chato) as it has been