Harecastle Tunnel

Harecastle Tunnel is a canal tunnel on the Trent and Mersey Canal in Staffordshire between Kidsgrove and Tunstall. It comprises two separate and parallel tunnels described as "Brindley" and the later "Telford" after the engineers who constructed them. The tunnel was built to transport coal to heat the kilns in the Staffordshire Potteries. At 1.5 miles (2.4 km) it was once one of the longest canal tunnels in Britain.Today only the Telford tunnel is navigable. The tunnel is only wide enough to carry traffic in one direction at a time and boats are sent through in groups, alternating northbound and southbound. Ventilation is handled by large fans at the south portal.Brindley TunnelThe Brindley tunnel was constructed by James Brindley between 1770 and 1777. Brindley died during its construction. At the time of its construction it was one of the two longest canal tunnels in Britain, together with Norwood tunnel, its twin Brindley, bore on the Chesterfield Canal.To construct the canal, the line of the tunnel was ranged over the hill and then fifteen vertical shafts were sunk into the ground. It was from these that heads were driven on the canal line. A major problem was the change in the rock type which ranged from soft earth to Millstone Grit. The construction site was also subject to flooding regularly, a problem which was overcome by the construction of steam engines to operate the pumps. Stoves were installed at the bottom of upcast pipes to overcome the problem of ventilation.