The Canary Islands began to emerge from the ocean depths as a consequence of magmatic activity. The process of formation began in the Miocene Age, about 23 million years ago.The oldest islands are La Gomera, Gran Canaria, Fuerteventura and Lanzarote, while the youngest are El Hierro, La Palma and Tenerife.
Since the end of the 15th century there have been 14 volcanic eruptions, the most recent in 1971 in the island of La Palma.
Important naturalists from past centuries, including Alexander von Humboldt, were interested in the islands, which nowadays are considered to be one of the most important volcanic regions in the world.
Almost all kinds of volcanic rock are present in the archipelago.
In the volcanic landscapes of the Canary Islands we can find cones, lava fields, craters, cliffs, as well as many caves and underground galleries, including one which is among the longest in the world at 6 km in length, as well as one of the ten longest volcanic tubes in the world, with a length of almost 20 km. Some exclusive endemic species in the islands inhabit the interior of these volcanic formations.
Mount Teide, the highest peak in Spain at 3,718 m., is the third biggest volcano on earth, measured from its base.