From Wikipaedia: "Avoncliff Aqueduct (grid reference ST803599) carries the Kennet and Avon Canal over the River Avon and the Bath to Westbury railway line, at Avoncliff in Wiltshire, England. It was built by John Rennie and chief engineer John Thomas, between 1797 and 1801. It is a Grade II* listed building.
During construction stone from a local quarry was used which broke when affected by frost. This caused buttresses to collapse and parts of the structure to need rebuilding. Eventually Bath stone from Bathampton Down was used enabling greater stability.
The aqueduct consists of three arches and is 110 yards (100.6 m) long with a central elliptical arch of 60 ft (18.3 m) span with two side arches each semicircular and 34 ft (10.4 m) across, all with V-jointed arch stones. The spandrel and wing walls are built in alternate courses of ashlar masonry and rock-faced blocks. The central span sagged soon after it was built and has been repaired many times.
As part of the restoration of the canal the aqueduct was lined with a concrete "cradle" and made water-tight in 1980."
During construction stone from a local quarry was used which broke when affected by frost. This caused buttresses to collapse and parts of the structure to need rebuilding. Eventually Bath stone from Bathampton Down was used enabling greater stability.
The aqueduct consists of three arches and is 110 yards (100.6 m) long with a central elliptical arch of 60 ft (18.3 m) span with two side arches each semicircular and 34 ft (10.4 m) across, all with V-jointed arch stones. The spandrel and wing walls are built in alternate courses of ashlar masonry and rock-faced blocks. The central span sagged soon after it was built and has been repaired many times.
As part of the restoration of the canal the aqueduct was lined with a concrete "cradle" and made water-tight in 1980."
