A mysterious series of hand-carved passages and chambers lies beneath the streets of Gilmerton. Once a small mining village, Gilmerton is now an Edinburgh suburb in the South of the city. No one knows why Gilmerton Cove exists but theories include a smuggler's lair, a Covenanter's refuge and a secret drinking den. It may have been built by an 18th century blacksmith called George Paterson. There are even suggestions it could be linked to the Knights Templar. There are different audio and visual displays to enjoy and you can decide for yourself which theory is correct. Tours last for one hour and must be booked in advance.