Journey to the centre of the Earth ...the fascinating caves under city’s ‘hollow mountain’
The beautiful Garth mountain, north of Cardiff, affords picturesque views, stretching for miles around. But far below its 1,007ft summit lies an underground network with a fascinating history, as Laura Clements reports
STANDING on the side of the Garth mountain, surrounded by tall and leafy beech trees and with views stretching over the rooftops of Cardiff and beyond, life seems peaceful and serene.
But don’t be fooled by this apparent tranquillity or the seeming solidity of the ground beneath your feet.
For the mountain holds one of Cardiff’s best-kept secrets – it’s hiding one of the biggest underground cave systems of any city in the UK.
Within those caves are even more secrets, some of which have occasionally been dragged to the surface, like the body of a murdered woman or the calcified skeletons of cats.
Others, like a blacksmith’s workshop still intact with all its tools in place and drowned by a subterranean lake, will never see the light of day again.
There are clues if you know where to look. From the rust-stained nodules half-buried in the woodland debris on the Garth to the now-disused ivy-clad quarry buildings scattered across the mountain, the secrets of Cardiff’s hollow mountain are hiding in plain sight.
They are the tiniest hints of what lies below – a labyrinth of uncharted tunnels, hidden chasms, bottomless pits, subterranean lakes and collapsed roofs left over from years of mining.
Nature was the original miner but was soon overpowered by the activity of man. The Garth mountain is just one part of a soft and porous band of carboniferous limestone hills that marks the southern edge of the coalfield and Cardiff’s northern limits.
Over time the mountain has been ravaged by those keen to exploit the mineral riches beneath their feet.
From Neolithic cave-dwellers to the Iron Age Celts, early Romans and fifth-century Welsh metal workers and right through to the 16th-century iron industry pioneers and the 19thcentury Pentyrch Ironworks, the mountain has been plundered for all it’s worth.
Even today the giant Mexican cement producer Cemex continues to work the Lesser Garth with the quarry works in Morganstown.
The steady march of modern-day quarrying has wrecked much of the Lesser Garth’s complex cave system. Yet the iron-working caverns in the Lesser Garth, first opened up in 1565 and saved from destruction by a local campaign in the 1980s, have survived with their own grisly tales to tell.
On November 2, 1963, a group of boys exploring the iron workings mine “looking for fossils” made a gruesome discovery when they came across the body of a young woman at the base of a shaft alongside one of the upper caverns.
She had been strangled, her body dumped into the shaft from some 200ft above. She was identified as Cardiff Bay sex worker Patricia Simpson, and the case became one of the oldest unsolved murders for South Wales Police at the time.
Despite an extensive hunt her killer was never found and the case went cold until fresh evidence led detectives to Israel in the 1990s.
A man, by this time in his eighties, had spent 15 years languishing in an Israeli jail for a separate manslaughter before confessing to the murder in Wales.
Despite calls for him to be extradited to Britain for questioning he was never brought back to the UK after he
The floor is usually coated with iron ore, ochre of very good quality. The walls are lined with beautiful crystals from a speck to an inch in diameter
FG EVANS
was released, a spokeswoman for South Wales Police told the Western Mail.
One of those who helped police search the caverns was film director Christopher Monger, who grew up in Taff’s Well and was familiar with the area.
Mr Monger thrust the Garth mountain of his homeland into the global spotlight after directing the 1995 film The Englishman Who Went up a Hill but Came down a Mountain, adapted from a book written by his parents.
Now living in the United States, Mr Monger can still recall just how vast the caves are: “It really is hard to comprehend how enormous these caverns were. And at the next level down there were enormous lakes.
“The caves looked golden because the yellow ochre dust covered everything. It was astonishing. We loved going there until a murdered woman was dumped there. That stopped the good feeling.”
People have always been entranced by the caverns, even when it was a hive of activity with men and boys labouring in the dark. In the late 1800s it was not uncommon for visitors to take day trips to the pits, by then owned by a TW Booker, to watch them at work.
Giving a talk to the Cardiff Naturalist Society in 1872, a Mr FG Evans spoke of “curious subterranean caverns” at the site.
He said: “The floor is usually coated with iron ore, ochre of very good quality. The walls are lined with beautiful crystals from a speck to an inch in diameter.
“The mines amply repay the trouble of inspection. Visitors are conveyed through the tunnel in a covered carriage kept for that purpose and carry a lamp to enable them to examine the sides of the rock as they go.”
During his descent to the bottom of the mine Mr Evans noticed a blacksmith shop that looked as if it was “suspended in mid-air”. Far below were the twinkling lights of the candles as the miners blasted the rocks.
Cave divers today say that very same blacksmith shop is still there, intact with all its tools in place, deep inside the now-flooded caverns. It’s as if someone has pressed pause on this bygone era, a silent snapshot of toil and industry left suspended in perpetuity.
While it is the jaw-dropping scale of the iron-working caverns which capture the attention, the series of caves beyond have long attracted cavers to the area.
The Lesser Garth Cave, hidden above the Ty Nant pub car park in Morganstown, is home to the extremely rare white cave spider Porrhomma Rosenhaueri. Also known as Ogof Tynant, it opens out into gigantic chambers and evidence suggests it has been used by humans for millennia.
The cave joins up to another, Ogof Ffynnon Taf, which is almost 400m in length and the largest cave system in the area. When it was first discovered by quarrymen in 1986 they found the skeleton remains of cats. Two were very old and one was “cemented” to the rock by natural calcification. The mystery of how and why cats found their way deep underground remains to this day.
The dripping water in these caves has created fascinating patterns over time. There are clusters of small fanlike curtains in the entrance and splendid stalactite pillars more than 20ft long. There are also crystal pools deeper within.
Standing amid the 114-acre beech woodland, it’s difficult to imagine just how much history is contained within one small mountain. Today the sound of hammers chipping away at rock below ground has been replaced by the low and constant hum of the M4 above ground.
But if you know where to look there are obvious signs the wood wasn’t always so quiet.
Perhaps there are many more secrets yet waiting to be discovered in this hollow mountain.