Me being on Tenerife had to visit this previously active volcano. Since it used to spew lava around the years of 1600 and 1700, the area is covered with dry solid pieces of lava.
Near the top you can see several mountain peaks close to eachother which used to be separated volcano's such as el Teide and el Pico. This all after the whole top used to be one big crater of an incredible 16 kilometers of diameter. Still today you can see on the south side the strong borders of the old crater like a long dike all around this mountain top.