Worsley Navigable Levels

Coal extraction was known in the area from as early as 1376 but large-scale development was left until the tenure of Francis Egerton, 3rd Duke of Bridgewater.

This sough was sited to provide drainage for as many mine works as possible in order to make its construction economic.

This solution to the water drainage problem was successful and extensions of 450 yards (410 m) proceeded to allow other coal seams to be drained.

It was clear to Francis Egerton and John Gilbert that the Duke of Bridgewater's coalmines would need to be much more efficient and productive in order to meet the rise in demand for coal in Manchester.

The first workable seam (the Worsley Four Foot mine) was reached in 1761, 770 yards (700 m) from the tunnel's portal.

In order to ease the congestion resulting from the large number of boats using the level a second entrance tunnel was dug, 500 yards (460 m) long, and a one-way system introduced.

A sloped branch was driven from the upper level to the surface at a gradient of 1 in 4 to allow boats to be drawn up and lowered down.

[1] Coals were moved between levels using vertical shafts until 1797, when an underground canal inclined plane started in 1795 was completed.