Inside Scotland's ancient Bone Caves

A view to the limestone cliffs near Inchnadamph

High on a limestone cliff in the north west Highlands are caves that have fascinated visitors to the area for at least 135 years.

The first scientific excavations of the Bone Caves at Creag nan Uamh, by geologists Ben Peach and John Horne in 1889, uncovered remains of Arctic animals and also evidence the caves were used by hunters about 8,000 years ago.

In the years since Peach and Horne, discoveries have included large chambers, an underground passage known to be at least 2 miles (3km) long - and a 20,000-year-old polar bear bone.

Speleologists - experts in cave exploration - believe further finds could be made in the area near Inchnadamph in Assynt.

A rocky trail leads to the imposing cliff at Creag nan Uamh and its four main caves.

There is a warning along the way of the potential risk of rock falls and the ground drops steeply away on one side of the narrow path as it nears the cliff.

At the entrance to the caves, water drips down from the sheer rockface above.

There are views out over the barren hills to the valley below and the rushing waters of Allt na Uamh stream.

The area's system of caves was formed 200,000 years ago before the landscape was changed by the last ice age, which ended about 15,000 years ago.

Over the last 135 years the landscape - and what lies beneath it - has fascinated geologists and palaeontologists

Peach and Horne's discoveries in the caves included bear and reindeer bones.

More recent investigations found the remains of other animals that are long extinct in Scotland such as lemming, wild horses, lynx and wolf.

Some of the wildlife - including a polar bear- is believed have been washed into the caves.

Major discoveries were made in 1967, when Kendal Caving Club explored a passage its members named Uamh an Claonaite.

Further underground areas were dived in 1975 and - by Grampian Speleological Group - in 1995.

Uamh an Claonaite is currently estimated to be about two miles long but could potentially extend further.

Flooding is one of the many obstacles and hazards which hamper exploration of the area's underground systems.

But Alan Jeffreys of Scotland's oldest caving club - Grampian Speleological Group - said there is still scope for new discoveries.

'Unsuspected territory'

"Passages lying some 20m beneath the Bone Caves might be extended in the future and perhaps even more passages might be found running north along the flank of Breabag (a nearby mountain).

"There is everything to play for."

He added: "Our members have also opened a new cave system in the riverbed in the north fork of the Allt nan Uamh valley.

"This reveals that a possibly extensive network of phreatic passages, formed when completely full of water and now filled with glacial debris and mud, could lead us into some major, previously unsuspected territory."

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Related internet links

• Grampian Speleological Group