THERE are tales of caves woven throughout Scottish history and folklore, from Robert the Bruce and the spider to stories of grisly discoveries, sleekit smugglers and spooky hauntings.

Here, we delve into the subterranean secrets of five fascinating caves.

The Bone Caves, near Inchnadamph, Sutherland

Victorian geologists John Horne and Ben Peach stumbled across a collection of animal bones here in the late 19th century. Further excavations of the caves uncovered remains belonging to wolves, lynx, Arctic foxes and even a polar bear, believed to date from the last glacial period.

Human bones and artefacts have also been discovered. The Bone Caves are two miles south of Inchnadamph on the A837 and easily accessed on foot along a mile-long path.

Visit nature.scot

The caves at Culzean Castle, Ayrshire

There's no shortage of spine-tingling anecdotes about the labyrinth of caves beneath Culzean Castle.

Evidence of human activity from the Iron Age has been found here.

HeraldScotland: Caves at Culzean Castle. Picture: National Trust for ScotlandCaves at Culzean Castle. Picture: National Trust for Scotland

During the 17th and 18th centuries, illicit wares, such as port, claret, rum and tea, were smuggled in to be sold locally.

The caves have a resident ghost, reputed to be a piper who mysteriously vanished. Organised hard-hat tours of the smugglers' caves will recommence next year.

Visit nts.org.uk

St Ninian's Cave, near Whithorn, Dumfries and Galloway

This small, secluded sea cave is said to have been a retreat of St Ninian, Scotland's first saint in the 4th century.

From the early Middle Ages, St Ninian's Cave has been a place of pilgrimage.

HeraldScotland: St Ninian's Cave. Picture: Historic Environment ScotlandSt Ninian's Cave. Picture: Historic Environment Scotland

An excavation discovered Christian symbols, including carved headstones and crosses from the 10th and 11th centuries, now displayed in nearby Whithorn Priory and Museum.

The cave is currently closed to allow for conservation work.

Visit historicenvironment.scot and visitscotland.com

Spar Cave, near Elgol, Skye

There is an elegant grandeur to Spar Cave with its flowstone staircase, limestone columns and glittering pools.

Sir Walter Scott visited in 1814 and later referred to it in his poem, The Lord of the Isles, as a "mermaid's alabaster grot." In 2014, Ben Stiller and Bear Grylls spent the night here for a TV survival show.

The cave is only accessible at low tide. Check tide times before visiting. Even better, book a local walking guide or a kayak tour.

Visit skyehighlandadventures.co.uk and skyakadventures.com

Sawney Bean's Cave, near Ballantrae, Ayrshire

According to legend, Sawney Bean was leader of a cave-dwelling, cannibalistic clan in the 16th-century that dined upon the flesh of more than 1,000 victims in this little corner of Ayrshire.

There's long been debate about the veracity of this story, yet its ghoulish macabre continues to inspire novels, plays and films.

HeraldScotland: An illustration of Sawney Bean outside his caveAn illustration of Sawney Bean outside his cave

Sawney Bean's Cave is located at Bennane Head, between Ballantrae and Girvan, just off the A77.

Immerse yourself in a Cannibal's Cave homage to Bean at the Edinburgh Dungeon.

Visit thedungeons.com