Mr. Begg sank the first two pits at Llwynypia from 1861 for a company run by Archibald Hood. Hood purchased Trealaw colliery and he renamed it Llwynypia No. 3. Nos. 2 and 3 were used for winding and No. 1 was the upcast.

In the early 1870's another two shafts were sunk, No. 5, which became the upcast for No. 3 and No. 4 for pumping, later No. 6 was added. By this time the company went by the name the Glamorgan Coal Company.

No. 3 pit worked the No. 3 Rhondda seam and the coal it produced supplied the collieries coking plant, where high quality "Hoods Coke" was manufactured. Later when the No. 3 Rhondda seam became exhausted, a level was driven close to the No. 5 pit to work the No. 2 Rhondda seam.

The colliery was also famous for making bricks. Women using hand moulds produced up to 10,000 per day.

In 1896, No. 3 House coal and Nos. 1, 2 and 6 steam coal employing a workforce of 2,331 in total.

The Cambrian Combine Company took over the running of the colliery in 1907.v By 1913 the number employed here had increased to 3,907.

A disaster occurred at this colliery in 1932 killing eleven men and boys.

Only Nos. 1 and 2 pits remained open by 1938 employing 560 men.

The Glamorgan Colliery was known locally as 'The Scotch' after the Scottish miners brought to the area by Archibald Hood in 1862.

With the Miners' Library and Institute on the right.  It was later integrated into the Cambrian Combine and was the scene of violent clashes during the Tonypandy Riots of 1910-11.

The Library has recently been demolished and all that is left is a statue of Archibald Hood, pointing to what was his creation

The colliery closed in August 1945 but was maintained for pumping until 1966.

The pumphouse is still standing and, even though it is classed as a protected building of historical importance it is slowly falling apart.