Tan Hill, North Yorkshire

Tan Hill (NY896067) is a high point on the Pennine Way in the Richmondshire district of North Yorkshire, England. It lies north of Keld in the civil parish of Muker, near to the borders of County Durham and Cumbria, and close to the northern boundary of the Yorkshire Dales National Park. It is in an isolated location, with the nearest town of Kirkby Stephen being an 11-mile (18 km) drive away.

Within the Pendleian, the lower subsystem of the Carboniferous structure, exists the Upper Howgate Edge Grit, a coarse-grained sandstone. Found in the peaks of the highest fells of North Yorkshire, the shale layer containing coal is found above it. The shale under the northwest region is call the Tan Hill seam, which was worked from the 13th century until the early 1930s.

The first records of coal being produced exist from 1384, when locally worked shallow shafts produced coal for Richmond Castle. The coal found was a poor-quality crow coal, which produced a dirty, dusty fuel. But local farmers wives preferred it as, when mixed with peat, it gave a good glow, was easy to stack up over night, and easy to revive in the morning. Before the start of the Industrial Revolution, the easily accessible upper seams were mainly worked out, requiring investment in deeper shafts. By the 17th century the poor-quality coal was locally converted in simple beehive kilns into coke – known locally as "cinders" – which was used in lead and iron smelting.

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