Narrow boat

A narrowboat or narrow boat is a boat of a distinctive design, made to fit the narrow canals of the United Kingdom.

In the context of British Inland Waterways, "narrow boat" refers to the original working boats built in the 18th, 19th, and 20th centuries for carrying goods on the narrow canals (where locks and bridge holes would have a minimum width of 7 feet (2.13 m); some locks on the Shropshire Union are even smaller). The term is extended to modern "narrowboats" used for recreation and more and more as homes, whose design and dimensions are an interpretation of the old boats for modern purposes and modern materials.

Purists tend to write the term with a space (narrow boat) when referring to an original (working) boat or a replica, omitting the space when referring to modern canal boats of around 7-foot (2.13 m) beam and used for leisure including residence. The single word 'narrowboat' has been adopted by authorities such as the Canal and River Trust, Scottish Canals and the magazine Waterways World to refer to all boats built in the style and tradition of the narrow canal locks.

Although some narrow boats were built to a design based on river barges and many conform to the strict definition of the term, it is incorrect to refer to a narrowboat (or narrow boat) as a barge. In the context of the British inland waterways, a barge is usually a much wider, cargo-carrying boat or a modern boat modelled on one, certainly more than 7 feet (2.13 m) wide.

It is also incorrect (or at least incongruous) to refer to a narrowboat as a longboat, although this name was sometimes used in the Midlands in working-boat days.

Usage has not quite settled down as regards (a) boats based on narrowboat design, but too wide for narrow canals; or (b) boats the same width as narrowboats but based on other types of boat.

The key distinguishing feature of a narrowboat is its width which must be less than 7 feet (2.13 m) wide to navigate British narrow canals. Some old boats are very close to this limit (often built 7 feet 1 ¹⁄₂ inches or 2.17 metres or slightly wider), and can have trouble using certain narrow locks whose width has been reduced over time because of subsidence. Modern boats are usually produced to a maximum of 6 feet 10 inches (2.08 m) wide to guarantee easy passage throughout the complete system.

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Wikipedia