This is absolutely must see! Cable car up to Teide is really a fun and you reach 3550m level. You need special permission if you want toclimb to the top of the Teide, but it's free of charge. You need to apply this special permission two to three months is advance. Be prepared that cable car is sometimes closed due to weather conditions for example due to heavy wind. If you reserve cable car tickets in advance from original website it's quite easy to change tickets for another day. If you give your contact information during reservation you will receive notify by e-mail if cable car is closed due to weather conditions. On morning reserve warm clothes, because temperature can be nearby zero Celsius degree, but on afternoon temperature is much higher, maybe 15 to 20 Celsius degree if sun is shining. Reserve also hat, sunglasses and proper shoes, because paths are rocky. View from Teide is really amazing!