The word Fogou 'foo-goo' is believed to come from the Cornish word for cave. Though only appearing in text in the 1500s, it is thought they originate from the Iron Age. They are exclusively found in West Cornwall, however other souterrains with some similarities exist in Brittany, Southern Ireland and northern Scotland. Each fogou is entirely unique, with no clear patterns except they they lie underground with a cut and cover building technique, lined with corbelled walls and capped with large granite lintels. One of their most intriguing features are their 'creep passages', small apertures that provide entry or exit into the fogou only by crawling low on your hands and knees or belly.