Maerdy is a village and community (or civil parish) in the county borough of Rhondda Cynon Taf, and within the historic county boundaries of Glamorgan, Wales, lying at the head of the Rhondda Fach Valley.
The area grew from a farming community to town around the coal mining industry and the development of Mardy Colliery in the late 19th century, but its last pit (Mardy Main) shut in 1990. The population in the UK census of 2011 was 3,160.
The first three maps are provided by A Vision of Britain through Time
These maps were found on Wikimedia Commons
These maps of Glamorgan post-1974 were found on another site and are very useful for sorting out the up-to-date geography of the area