The age of the main subaerial shield phase for Tenerife is about 5 million years. Volcanic cones can be found distributed irregularly over the whole island' surface and contribute to the amazing landscape. Its geographical surface is almost perfectly triangular. Its vertexes are represented by Punta de Anaga in the Northeast, Rasca in the South, and Teno in the Northwest. The geographical contours respond to a very simple general scheme: a central mountain range ("Cumbre Dorsal") which crosses its axis from the Northeast to the Southeast, of progressive heights which culminate in Las Cañadas with inclined slopes toward each side, plyed by deep "Barrancos" (= gorges). Its volume could be compared to a tetrahedron, which superior vertex is cut by the Las Cañadas platform, in which centre emerges the Teide cone with 3.718 m. This basic geography is the result of the volcanic activity which has taken place ever since the Tertiary period in an almost uninterrupted manner, with volcanic eruptions. The main crater has been the one in Las Cañadas with different eruptional periods. The Anaga and Teno spurs are separated from the common genesis of the rest of the island since they belong to more ancient eruptions.
The Anaga mountain
range, in the North-Eastern part of the island is formed by a thin summit, from
which numerous and deep gorges stand inclining toward its two sides making it look like a
fish bone. The South-Western spurs of the Anaga range and the end of the dorsal Teide
range is found in the 600 metre Los Rodeos deep ground and greatly humid plateau, which
falls in a wide ramp in a South-Eastern direction toward the coast. It is here where Santa
Cruz - the capital of the island - lies next to the sea, and also where the La Laguna
plateau is situated. The dorsal mountain range is born on this plateau, it rises from La
Esperanza (966 m) and continues all the way up to the astronomical observation station at
Izaña (2.362 m), where it branches off North and South to form the walls of Las Cañadas
del Teide, which crowns the island as the center point of the National Park of
extraordinary geological and botanical wealth.Las Cañadas and El Teide
Las Cañadas are an impressive flat volcanic crater of almost 10 km in diameter and 75 km in perimeter, at an altitude of
between 2.000 to 2.150 m over sea-level. It covers an area of almost 13.000
hectares. At the Western edge of Las Cañadas rises the volcano El
Teide , which can be seen from all islands. El Teide is the third largest volcano
on Earth and the highest in the Atlantic Ocean. Like its brothers, the Mauna Loa and the
Mauna Kea (the first and second largest volcanoes on earth), it represents a shield
volcano. Elevation at the summit of the volcano, the so-called Pico del Teide (= Teide
peak) is 12.210 feet (3.718 m), which makes it the highest point of Spain. From the
basis of the Cañas depression the cone rises more than 1.700 m. The depression was formed
by a combination of an explosive emptying of a high-level magma chamber and a successive
collapse and lateral movement of the summit. The volcano is still active, the most recent,
tremendous eruption of the volcano was on its Northwest flank only 90 years ago in 1909,
which filled about 1/4 of the Southern parts of Las Cañadas with lava. 
