Ystrad Mynach is a town in the Caerphilly County Borough, within the ancient county of Glamorgan, Wales, and is north of the town of Caerphilly. The urban area has a population of 19,204, and stands in the Rhymney Valley. Before the Industrial Revolution and the coming of coal mining in the South Wales Coalfield the valley was rural and farmed. It lies in the community of Gelligaer. Etymology In the Welsh language, is a wide flat bottomed valley and means "monk". The form is sometimes found in historical records, which Hywel Wyn Owen states is a dialect form of . As there is a lack of evidence for monks settling in the area, the word may have been the name of a tributary of the Rhymney River. It has been suggested that, rather than referring to a monastic institution, is "place" + , a suffix associated with the names of marshy floodplains, also found in nearby Llanbradach and Llancaiach. Prior to erection of defences on the River Rhymney in the 1960s the town was indeed subject to periodic flooding. Amenities and history The town houses a number of council offices, as well as the Ystrad Mynach campus of Coleg y Cymoedd, a further education college established in 1959 to provide training for local coal miners and merged with neighbouring Coleg Morgannwg to form Coleg y Cymoedd in 2013. The nearby Penallta Colliery was the last coal mine to close in the valley. Other notable buildings and structures are the Ystrad Mynach railway station, opened in 1890, the viaduct, a sculpture to commemorate the areas industrial heritage, a community hospital, a number of schools, and the Beech Tree, Coopers Arms and Royal Oak pubs. From 1927 to 1996, Ystrad Mynach hosted the 'F' division headquarters of Glamorgan Constabulary (from 1968, South Wales Police). Ystrad Mynach railway station was a location for one of Ronnie Barker's Porridge episodes. Records show that Ystrad Mynach railway station was in existence in 1857, when it was known as Ystrad Junction. A new Local General Hospital Ysbyty Ystrad Fawr was opened in late 2011. Work started on the Ystrad Fawr site in September 2007. It is located between the A469 Caerphilly to Newbridge Road and the old Caerphilly Road between Ystrad Mynach and Llanbradach. This replaced the services provided by the previous Ystrad Mynach Hospital. Situated to the north of Ystrad Mynach, is a collection of