Tunnels thought to be dug out hundreds of years ago by medieval monks were discovered by accident, as work began to convert a former cattle shed into a restaurant.
Running for about a mile underneath Park Farm on the banks of the Union Canal, near Linlithgow, in West Lothian, the mysterious underground passages left archaeologists stunned.
They were discovered by accident in 2005 by local farmer Peter Waddell, who told the press at the time that the elaborate construction reminded him of the catacombs in Rome.