The volcanoes featured in the NOVA program "Volcano's Deadly Warning"—Galeras, Nevado del Ruiz, Popocatepetl, and Mt. Redoubt—as well as many other famous volcanoes, including Mt. St.

It is 2,600 feet deep, or nearly half a mile. As seismic activity within the volcano increases, the crater periodically contains an active lava lake that can drain suddenly and catastrophically ...

"I always marvel that we've been doing human anatomy and gross anatomy for hundreds ... to around three million people living close to the volcano, including metropolitan Naples.” ...