A greenway is "a strip of undeveloped land near an urban area, set aside for recreational use or environmental protection". However, the term can in fact include "a scenic road" and though many are in urban areas, there are some rural greenways, as for example the Monadnock-Sunapee Greenway, a hiking trail in southern New Hampshire.
A greenway is a trail (and sometimes a wildlife corridor), found in both urban and rural settings, that is frequently created, out of a disused railway, canal towpath, utility, or similar right of way, or derelict industrial land. Rail trails are one of the most common forms of greenway, and they also resemble linear parks.
In Southern England the term also refers to ancient trackways or green lanes, especially those found on chalk downlands, like the Ridgeway.
The American author Charles Little in his 1990 book, Greenways for America defines a greenway as
The term greenway comes from the green in green belt and the way in parkway, implying a recreational or pedestrian use rather than a typical street corridor, as well as an emphasis on introducing or maintaining vegetation, in a location where such vegetation is otherwise lacking. Some greenways include community gardens as well as typical park-style landscaping of trees and shrubs. They also tend to have a mostly contiguous pathway. Greenways resemble linear parks, but the latter are only found in an urban and suburban environment..
Though a wild life corridors are also a greenways, because they have conservation as their primary purpose, they are not necessarily managed as parks for recreational use, and may not include facilities such as public trails.
Tom Turner analyzed greenways in London, looking for common patterns among successful examples. He was inspired by the pattern language technique of architect Christopher Alexander. Turner concluded there are seven types, or 'patterns', of greenway which he named: parkway, blueway, paveway, glazeway, skyway, ecoway and cycleway.