Volcanoes have terrorized Civilizations for millennia. Most famous is the composite volcano Somma-Vesuvius, active for over 25,000 years, which destroyed the towns of Pompeii and Herculaneum in August of 79 AD. The volcano erupted hundreds of times before going into repose in 1944. When scientists of the 21st century finally were able to harness the geothermal power of the volcano, they discovered one of the most valuable sources of power and industry.