This gives details of all known South Wales collieries on a fully searchable CD included with the book. The book itself contains a series of maps that locate each colliery and a selection of photographs to give a flavour of the coalfield. In writing this book the author consulted many reference sources to enable all of the information to be collated together for the first time across an entire coalfield. The information given includes all relevant dates, ownership details and changes, selected output figures and manpower, together with site maps where possible.