a person who is in charge of a lock on a canal or river, and opens and closes the gates See related entries: Rivers and lakes CulturecanalsBritain's canals (= man-made channels of water for boats to travel along) were built in the late 18th and early 19th centuries, at the start of the Industrial Revolution. They provided a cheap and convenient means of transport for heavy goods, especially between the mining and industrial centres of the Midlands and north-west England. Coal, grain, clay and other materials were transported on narrowboats, also called barges, that were pulled along by horses walking along a towpath beside the canal. Many miles of channel had to be dug, with some sections passing through tunnels or over aqueducts (= long, high bridges across valleys). Hundreds of locks were built to enable boats to go up or down a hill. A flight (= series) of 20 or 30 locks was needed on some steep sections.In the US canals were used for a short period to transport goods to areas where there were no large rivers. The most famous, the Erie Canal in New York State, ran from Buffalo on Lake Erie to Albany on the Hudson River and connected New York City with Ohio, Michigan and Pennsylvania. Mules, not horses, were used to pull the barges. The growth of the railway in the 1840s soon took business away from the canals, but the canal system played an important role in expanding trade and encouraging people to move west.After the railways were built, many canals were filled in. In Britain especially, canals that still exist have become popular with people wanting a quiet country holiday away from traffic. Old narrow boats have been fitted with motors and converted to provide attractive holiday accommodation. Speed is restricted on canals so the pace is slow and restful. Some locks are operated by lock-keepers, but many are worked (= opened and closed) by people on the boats. Going through a flight of locks is seen as part of the fun. At night, people moor their boats at the side of the canal. Canals are also popular with fishermen, and with walkers using the towpath. Many pubs are built beside canals and attract people enjoying a canal holiday or having a day out.In Britain, some people live in narrow boats and stay most of the time on a particular stretch of canal. These houseboats are often painted in bright colours, with pictures of flowers on the side. On the flat roof there are sometimes traditional jugs and pots painted with similar designs.