Sapperton Tunnel, through which the Thames and Severn Canal flows, is 2·17 miles, 3,817yds or 3·49 km long.
The tunnel burrows under the highest part of the Cotswold Hills and, at its deepest point, is 70yds or 65m below ground.
The tunnel was completed on 20th April 1789 and at that time was the longest tunnel ever dug in England.
The Thames & Severn Canal, as its name implies, formed a link between the two rivers.
To the west, through the tunnel, the canal joined the Stroudwater Navigation at Wallbridge in Stroud.
The Stroudwater Navigation then continued to the River Severn at Framilode.
To the east the canal joined the River Thames at Inglesham near Lechlade. Despite problems with the construction and water supply, the canal and Sapperton Tunnel remained in use until the early 1900s.
This section of the Thames and Severn Canal was abandoned in 1927.
Roof falls in the brick lined sections of the tunnel now block the middle and Daneway end.
Click here to view the results of Nick Bird’s detailed research into the tunnel.
Sapperton Tunnel in cross section
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