TENERIFE The large triangular island of Tenerife is composed of a complex of overlapping Miocene-to-Quaternary stratovolcanoes that have remained active into historical time. The NE-trending Cordillera Dorsal volcanic- massif joins the Las Cañadas volcano on the SW side of Tenerife with older volcanoes, creating the largest volcanic complex of the Canary Islands. Controversy surrounds the formation of the dramatic 10 x 17 km Las Cañadas caldera, which is partially filled by 3715-m-high Teide stratovolcano, the highest peak in the Atlantic Ocean. The origin of the caldera has been variably considered to be due to collapse following multiple- major explosive eruptions or as a result of a massive landslide (in a manner similar to the earlier formation of the massive La Orotava and Guimar valleys), or a combination of the two processes. The most recent stage of activity beginning in the late Pleistocene included the construction of the Pico Viejo and Teide edifices. Tenerife was perhaps observed in eruption by Christopher Columbus, and several flank vents  on the Canary Island's most active volcano have been active during historical time. (Global Volcanism Program) Teide Location: 28.271° N, 16.641° W Elevation: 3.715m lava flows on the slopes of Pico Viejo Teide National Park fumaroles in summit crater  Pico Viejo viewed from the summit of Teide- in backround  La Gomera Pico Viejo and Teide fumaroles in summit crater summit crater of Teide summit of Teide 3715m Photo NASA trail to the summit of Teide Photos: Rolf Cosar Tenerife, Febr. 1983 HOME click on photos