On the Kennet & Avon Canal, between Crofton Lock and Wootton Top Lock you'll find the Bruce Tunnel - the only 'proper' tunnel on the Kennet & Avon Canal (there are two at Sydney Gardens in Bath which are just over 50 metres long, so really not much wider than a bridge). It was built between 1806 and 1809 on the insistence of Thomas Brudenell-Bruce who was the 1st Earl of Ailesbury and who owned the land through which the proposed canal would pass.
There is no towpath through the tunnel, so in the times before engines, when horses were used to pull the canal barges along, the horses would be unhitched, walked along to the other end of the tunnel to meet the boat and then rehitched to continue the journey. In order to be able to pass through the tunnel, a chain was installed for the full length of the tunnel (all 502 yards) which the boatmen would have to pull in order to haul the boat through to the other end. It must have been hard work!
These days the chain is not used for this purpose except in the event of engine failure or similar problem so it remains in place as a safety measure. However it is not in the best of condition and will have to be replaced shortly but the estimated cost of this – just the chain - is something like £8000. Canals are expensive to maintain!
The tunnel passes under part of Savernake Forest as well as Savernake Low Level Station (closed in 1966) which was on the Berks & Hants Extension Railway, now GWR. David Newman and Nicholas Hopkins who volunteer for the Canal & River Trust, have been investigating this symbiotic relationship between the canal and the railway and have found some fascinating features and stories now available in this leaflet.