John Rennie
John Rennie (1761-1821) was one of the celebrated grandfathers of the canal network, whose waterways underpinned Britain’s Industrial Revolution.
Rennie was a prolific engineer, from what the English Heritage Book of Canals calls the ‘heroic’ phase of canal construction. The waterways he built include the [Lancaster Canal], the [Kennet & Avon Canal], the [Aire & Calder Navigation], the [Fossdyke Canal], the Crinan Canal and the [Rochdale Canal]. These canals brought about unprecedented changes in Britain’s industry, allowing goods and raw materials to be transported from industrial heartlands, around the country and to the rest of the world.
Iconic and large-scale
Nigel Crowe, the Canal & River Trust’s head of heritage, says: “The hallmark of Rennie’s canals is imaginative, large-scale planning. Rennie’s leadership was inspired; the engineering of his canals was bigger, better and bolder than his predecessors. He was one of the first of the truly ‘modern’ British engineers.”
Rennie’s structures carried canals across valleys, up hills and through solid rock. He helped create some of the most iconic and loved canal structures. His masterpieces include the [Caen Hill Lock Flight] on the Kennet & Avon Canal and the [Lune Aqueduct] on the Lancaster Canal.
Nigel says: “His great aqueducts on the Kennet & Avon Canal and the[ Lancaster Canal] are not only triumphant works of engineering but triumphal arches that celebrate the classical Georgian age he lived in.”
He adds: “Rennie’s canals are characterised by repeated, ‘mass-produced’ standard designs; like the endless series of elegant stone bridges on the Lancaster Canal, which are a pleasure to come across, one after another.”
London Bridge
Rennie was also responsible for designing and building docks in Liverpool and London, as well a Rudyard Reservoir in Staffordshire. He created some of the country’s finest bridges including Waterloo and Southwark Bridges, where he combined stone with new cast-iron techniques. He designed old London Bridge, which was built after his death by his son (also named John Rennie). This bridge was dismantled in 1967, and reconstructed in Lake Havasu City, in Arizona, USA.
Although best known for waterways structures, Rennie was multi-talented. He also designed an early dredging machine and was a pioneer of diving equipment.

