<P> The modern canal system was mainly a product of the 18th and early 19th centuries . It came into being because the Industrial Revolution (which began in Britain during the mid-18th century) demanded an economic and reliable way to transport goods and commodities in large quantities . </P> <P> By the early 18th century, river navigations such as the Aire and Calder Navigation were becoming quite sophisticated, with pound locks and longer and longer "cuts" (some with intermediate locks) to avoid circuitous or difficult stretches of rivers . Eventually, the experience of building long multi-level cuts with their own locks gave rise to the idea of building a "pure" canal, a waterway designed on the basis of where goods needed to go, not where a river happened to be . </P> <P> The claim for the first pure canal in Great Britain is debated between "Sankey" and "Bridgewater" supporters . The first true canal in the United Kingdom was the Newry Canal in Northern Ireland constructed by Thomas Steers in 1741 . </P> <P> The Sankey Brook Navigation, which connected St Helens with the River Mersey, is often claimed as the first modern "purely artificial" canal, because although it was originally a scheme to make the Sankey Brook navigable, it included an entirely new artificial channel that was effectively a canal along the Sankey Brook valley . However, "Bridgewater" supporters point out that the last quarter - mile (400 m) of the navigation is indeed a canalised stretch of the Brook, and that it was the Bridgewater Canal (less obviously associated with an existing river) that captured the popular imagination and inspired further canals . </P>

What is the oldest canal in the uk