19th century thumb|right|American canals Competition, from railways from the 1830s and roads in the 20th century, made the smaller canals obsolete for most commercial transport, and many of the British canals fell into decay. Only the Manchester Ship Canal and the Aire and Calder Canal bucked this trend. Yet in other countries canals grew in size as construction techniques improved. During the 19th century in the US, the length of canals grew from to over 4,000, with a complex network making the Great Lakes navigable, in conjunction with Canada, although some canals were later drained and used as railroad rights-of-way.
19th century thumb|right|American canals Competition from railways from the 1830s and roads in the 20th century made the smaller canals obsolete for most commercial transport and many of the British canals fell into decay Only the Manchester Ship Canal and the Aire and Calder Canal bucked this trend Yet in other countries canals grew in size as construction techniques improved During the 19th century in the US the length of canals grew from to over 4000 with a complex network making the Great Lakes navigable in conjunction with Canada although some canals were later drained and used as railroad rights-of-way