'Secret' geology places

A set of ten 'secret' places for days out and things to see and do around the country that you may not have heard of before.


Creswell Crags | SK 537 744 | nearest towns Bolsover and Worksop

Creswell Crags is a limestone gorge, honeycombed with a network of caves that have formed as water has slowly dissolved away the limestone. Creswell Crags are famous for being the home of hunters during the last ice age 50 000 to 10 000 years ago and the only known site of Palaeolithic cave paintings in England. The story of the Crags is told in a museum at the site, and website Creswell Crags — Home of the Ice Age Hunter Zoom to this location on the map above

Hartland Point | SS 230 278 | nearest town Bideford

Hartland Point (click to enlarge).

The rocky cliffs and hidden coves around Hartland Point are known as the 'Wreckers Coast' because so many shipwrecks happened here in the past. But these cliffs also spectacularly display rock layers that have been folded into twisted shapes on a grand scale. These Carboniferous rocks were originally formed as mud and sand on the seabed, over 300 million years ago. In 1941, Hartland Point was a naval VHF radio intercept station for the 'Y service', a feeder service for the Enigma operation at Bletchley Park.

Whitby | NZ 900 110 | nearest town Whitby

Whitby (click to enlarge).

Whitby is renowned for the church of St Mary, whose churchyard on the East Cliff gave Bram Stoker the inspiration to write his world-famous book, Dracula. But the cliffs hold many other secrets. They are made up of Jurassic mudstones, which were laid down on the sea floor over 150 million years ago and contain fossils of ancient sea creatures, including ammonites, which can commonly be found along the beach.
The Whitby mudstones also contain the compressed fossilised wood jet, which has been used since the Bronze Age to make beads and jewellery, and reached a peak of popularity in the mid-19th century, after it was favoured as mourning jewellery by Queen Victoria.

Northern Ireland

Portrush Sill | ING 4857, 4409 | nearest town Portrush, Co. Antrim

Portrush Sill (click to enlarge).

Within walking distance of the promenade the rocky skerries and headland at Portrush are geologically infamous. During the 18th century these rocks were central to the debate about how molten rocks were formed. The 'Neptunists' thought that they crystallised from sea-water, while the 'Plutonists' believed it was the result of volcanic activity. The 'Plutonists' showed that fossils (ammonites) in the mudstone were baked by heat from the sill, and so won the argument! Today one can still see the hard sheet of basalt rock that was formed when magma (molten rock) was injected into mud on the sea floor. This sill was formed at the same time as the Giant's Causeway, during a major episode of volcanic activity, as the Atlantic Ocean began to open 60 million years ago.

The Ring of Gullion | ING 3027, 3200 | near Newry, counties Down and Armagh

The Ring of Gullion (click to enlarge).

Centered on the brooding mass of Slieve Gullion, the Ring of Gullion comprises a series of hills around six miles across. The Ring marks the position of a circular fracture in the Earth's crust into which molten rock moved, 60 million years ago, beneath an erupting volcano. It is just one of a number of ancient, eroded volcanoes scattered across Scotland and Northern Ireland.


Fossil Grove, Victoria Park | NS 538 673 | nearest town Glasgow

Victoria Park is home to some of the most spectacular fossil tree stumps in the UK, which were discovered in the base of an old quarry when the park was laid out in 1887, and which are now protected inside a building. The tree stumps are still in the position where they grew over 300 million years ago, when they were part of a vast, wet and steamy tropical forest that grew on thick peat bogs. After the trees died, the stumps were buried under river mud and sand, to be preserved as fossils. With time, heat and deep burial the peat became the coal seams that powered the Industrial Revolution.

Inchnadamph Bone Caves | NC 253 179 | near Ullapool

Inchnadamph Bone Caves (click to enlarge).

A walk up a beautiful limestone valley north of Ullapool brings you to the Bone Caves, in which remains of wolves, bears, lynxes and arctic foxes have been found. These animals took refuge in the caves tens of thousands of years ago, when Scotland's climate was much colder than it is now. A 2000-year-old walrus ivory pin, discovered in the caves, indicates that people were here during the Iron Age.

More information and map to The Bone Caves

Siccar Point | NT 812 709 | nearest town Eyemouth

Siccar Point (click to enlarge).

Siccar Point is one of the world's most famous geological sites, yet it lies hidden at the foot of a remote cliff in Berwickshire. It was here, in 1788, that James Hutton, the 'father of modern geology' recognised the vast extent of geological time — far beyond the then accepted age of the earth of 6000 years. He saw that vertically layered rocks at Siccar Point are partly covered by younger, flat-layered rocks. He reasoned that the vertical rocks were originally laid down as flat layers of sand on an ocean floor, and that it must have taken a long time — perhaps millions of years — for these to be folded and uplifted out of the water by earth processes and eroded into an irregular landscape, before the younger sandstones could be laid down.


Pontneddfechan |SN 915 080 | nearest town Glyn-neath, South Wales

The Pontneddfechan area combines outstanding natural landscape features with a diverse industrial heritage. The Carboniferous limestones, mudstones and sandstones have been fractured and twisted, giving rise to steep-faced crags and spectacular waterfalls and caves, and are host to abandoned mine entrances and quarries. According to local folklore King Arthur and his knights still slumber in an underground chamber awaiting the call to rise again and rescue Britain from the scourge of the Saxons.

Llanddwyn Island | SH 390 630 | nearest town Newborough, North Wales

Llanddwyn Island (click to enlarge).

The rocky foreshore around the tidal island of Llanddwyn displays spectacular examples of ancient pillowed and fragmented rocks which formed when lava enters the ocean. These features bear testimony to the power of plate tectonic forces and the destruction of an ancient ocean floor; a fitting geological backdrop for a place, which according to Welsh mythology, was home to the tragic St Dwynwen, the Welsh patron saint of lovers.