Tar Tunnel
The Tar Tunnel is located on the north bank of the River Severn in the Ironbridge Gorge at Coalport, England. It is one of ten Ironbridge Gorge Museums attractions administered by the Ironbridge Gorge Museum Trust.
Miners struck a gushing spring of natural bitumen, a black treacle-like substance, when digging a canal tunnel for the Coalport Canal in 1787. The plan, proposed by William Reynolds, was to connect the canal alongside the River Severn to the lower galleries of the mines below the Blists Hill area. After digging some 3,000ft (almost 1 km) into the hill the canal project was abandoned in favour of bitumen extraction.
The tunnel was a great curiosity in the eighteenth century and bitumen still oozes gently from the brick walls today. Bitumen's chief commercial use at the time was to treat and weatherproof ropes and caulk wooden ships, but small amounts were processed and bottled as 'British oil', a remedy for rheumatism.
After the canal project was abandoned the Hay Inclined Plane was built instead, its base being alongside the canal basin. After a few years of mining the bitumen supply was depleted and the tunnel was used for its original purpose, to move product from the mine systems of the area onto the canal ways.
Visitors are provided with hard hats and may enter the first 300ft (roughly 100 m) of the brick-lined tunnel as far as an iron gate. Electric lighting is provided.
Coordinates: 52°37′12″N 2°27′9″W / 52.62000°N 2.45250°W
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