The Gruta das Torres is located outside of Criação Velha, Madalena on the western slopes of Mount Pico. The cave is part of a pahoehoelava flow which originated from the Cabeço Bravoparasitic cone about 500 to 1500 years ago. It is the longest cave in the Azores at 5,150 meters with heights up to 15 meters.
The Azores Regional Government declared the cave a regional natural monument on March 18, 2004 (Monumento Natural Regional DLR N.° 6/2004/A). The Gruta das Torres is open to the public since 2005. The first 400 meters are accessible to visitors accompanied by a guide.
References
Áreas Ambientais dos Açores, Livro da Secretaria Regional do Ambiente e do Mar., 2005