Shrouded in mystery, this Spanish island and its sisters were suspected ports for German U boats and possible ‘ratline’ stops for escaping Nazis to South America. One house in particular, has many stories and structural features that belie the proposed agricultural purpose of the building. Built by a mysterious German engineer in an inhospitable location, the structure contains strange tunnels, a suspicious watch tower, an air strip, bunkers and a creepy hospital-like room. Was this a secret Nazi base for Uboat resupply, or were there even darker purposes for the house?