Freemining in the Forest.
In medieval, and earlier times, the extraction of coal from underground was very limited because of the high water table underneath the Forest. Mining techniques were comparatively primitive and most mines were started from outcrops of coal which followed the seam into the hillside along short drifts or levels or down a small pit until flooding prevented further digging. There were, in medieval times, military implications to the mining skills developed, however crudely by todays standards, by the miners of the Forest. There was a military need to mine, or dig under, an opposing castle - or even to counter-mine (dig under the tunnel of the attacking force). Once a tunnel had been dug under a castle wall the wall was weakened and would fall and later on in history its' fall was hastened with gunpowder. Hence the skills of Forest of Dean coal miners were in demand by the Crown forces.
Records show that as far back as 1253 twenty of the Forest of Dean coal miners were pressed into military service as part of a Gascon expedition led by the King. Both Edward II and Edward III took Dean miners on their forays into Scotland. Tradition has it that, as a reward for "Services Rendered" during the siege of Berwick and other places during the Scottish wars of the 14th century, Dean's miners acquired from the Crown the privilege to mine where they wished in the Forest - to be 'Free Miners'.
The tradition became ensconced in law and was formalised in the mid-19th century in what was called "The Book of Dennis" and in which were listed the various qualifications that were needed to be a Freeminer (eg., Born in the 'Hundred of St. Briavels', have worked for a 'year and a day' in a coal mine, iron mine or stone quarry etc.). These qualifications are still in force today. However - as, for example, due to the closure of the local hospital, most Foresters are now born outside the Forest, very few Foresters nowadays can qualify to be Freeminers.
Over the years coalmining in the Forest has changed from one and two-man pits scratching into the surface coal to deep mines being sunk by large companies employing many hundreds of local miners both above and below ground. Towards the end of the mining era the National Coal Board took over the pits. Economic factors have always militated against the Free miners in that the geology of the coalfield and its hydrology have made it dangerous and expensive to extract coal. This, accompanied by the hilly nature of the terrain and the isolation of the Forest from the rest of Enland and Wales - cut off by two major rivers (the Severn and the Wye), made transport of the coal very expensive. So the Forest of Dean has never really been able to compete with high grade coal from Wales or cheap coal from the Midlands or Overseas and the natural outcome of a rationalised national coal industry was the closure of the Forest of Dean field. This was achieved by the NCB in the 1960s - instantly plunging the Forest into an economic disfunction which it is still struggling to overcome.