 Engineer Thomas Telford improved both the design and quality of the material in bridges, for example, at Buildwas, upstream of Coalbrookdale, built in 1796, and also for aqueducts, such as the world-famous Pontcysyllte Aqueduct in North Wales, built in 1805, where both the arches and the trough are constructed of cast iron.On the continent, the 1804 Pont des Arts in Paris is an early and elegant use of cast iron for a major city river crossing (the metal work of the current bridge is a near identical copy built in 1984 due to structural decay).Another notable example is the elegant Ha'penny Bridge in Dublin, cast by the Coalbrookdale foundry, and built in 1816.