Dorothea Quarry commenced working in the early 1820s, though there were a number of smaller workings on or near the site before this. By 1848 it had become the dominant quarry in the area, employing 200 men and producing 5000 tons of finished slate. Production peaked in 1872 at 17442 tons. In the 1930s over 350 men were employed at Dorothea. Production dropped significantly after the start of World War II and the quarry closed in 1970.
Since quarrying ended in 1970, the Dorothea Quarry has flooded and become a popular site for scuba diving (even though there are no facilities provided, and diving is officially banned in the quarry); the unregulated nature and depth of the site has encouraged some divers to overestimate their capabilities – in the decade 1994-2004 21 divers lost their lives in the quarry.
A view of part of Dyffryn Nantlle with The Nebo Mast in the distance.
Part of the old Talysarn Town Hall/Plas Dorothea
Arch way into the plas..
Main entrance to the Large Plas/Mansion..
The cave
This cave goes for about 500 meters until it is stopped by a collapse its thought to be part of the old nantlle railway/tram way.
One of many old houses around the quarry...
There are two of these large structures, known as pyramids, at Dorothea,they served as bases for the chain inclines and allowed the waste rock to be tipped behind.
One of the Shed/Workshops in ruin..
At the beginning of the 20th Century, Dorothea quarry was urgently in need of a long term solution to the ongoing problem of keeping the workings, by then over 500 feet deep, free of water. It was decided to purchase a Cornish beam engine. An old but reliable technology. The engine was built by Holman Brothers and was the last but two ever built. It is also believed to be the newest Cornish beam engine still in existence. The engine was able to pump 10 gallons of water per second from a depth of over 500 feet. The engine started work in 1906 and served until 1951 when it was replaced by a 60hp electric pump. Apart from a brief period in 1956 the engine has been disused ever since.
The quarry Clock on the side of the Cornish Beam Engine House.
Furnaces..
One of the Two Pyramids.
View from top of one of the pyramids of Dorothea quarry pool in the foreground with the Cilgwyn quarry tips behind.
Some old photos of the quarry and pump house
Hope you Enjoyed My post, Thanks for viewing
Since quarrying ended in 1970, the Dorothea Quarry has flooded and become a popular site for scuba diving (even though there are no facilities provided, and diving is officially banned in the quarry); the unregulated nature and depth of the site has encouraged some divers to overestimate their capabilities – in the decade 1994-2004 21 divers lost their lives in the quarry.
A view of part of Dyffryn Nantlle with The Nebo Mast in the distance.
Part of the old Talysarn Town Hall/Plas Dorothea
Arch way into the plas..
Main entrance to the Large Plas/Mansion..
The cave
This cave goes for about 500 meters until it is stopped by a collapse its thought to be part of the old nantlle railway/tram way.
One of many old houses around the quarry...
There are two of these large structures, known as pyramids, at Dorothea,they served as bases for the chain inclines and allowed the waste rock to be tipped behind.
One of the Shed/Workshops in ruin..
At the beginning of the 20th Century, Dorothea quarry was urgently in need of a long term solution to the ongoing problem of keeping the workings, by then over 500 feet deep, free of water. It was decided to purchase a Cornish beam engine. An old but reliable technology. The engine was built by Holman Brothers and was the last but two ever built. It is also believed to be the newest Cornish beam engine still in existence. The engine was able to pump 10 gallons of water per second from a depth of over 500 feet. The engine started work in 1906 and served until 1951 when it was replaced by a 60hp electric pump. Apart from a brief period in 1956 the engine has been disused ever since.
The quarry Clock on the side of the Cornish Beam Engine House.
Furnaces..
One of the Two Pyramids.
View from top of one of the pyramids of Dorothea quarry pool in the foreground with the Cilgwyn quarry tips behind.
Some old photos of the quarry and pump house
Hope you Enjoyed My post, Thanks for viewing
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