Monumento Natural del Tubo Volcánico de Todoque Nature · Los Llanos de Aridane, La Palma, Santa Cruz de Tenerife Image of Los Llanos de Aridane, not of the place itself. Also known as the Cueva de Las Palomas, it is a gallery around 3 metres wide and just over 500 metres long, formed by the draining of lava from the San Juan volcano in 1949. It is protected as a Monumento Natural within the Canary Islands Network of Protected Natural Areas for its geological interest and for being home to invertebrate fauna adapted to life in darkness; visiting it requires caving equipment and a specialist guide. 1949 Photo: Benjamín Núñez González (CC BY-SA 4.0) What to see and do in Los Llanos de Aridane