A linear park is a park in an urban or suburban setting that is substantially longer than it is wide. Some are rail trails ("rails to trails"), that is disused railroad beds converted to recreational use, while others use of strips of public land next to canals, streams, extended defensive walls, electrical lines, highways and shorelines. They are also often described as greenways. In Australia, a linear park along the coast is known as a foreshoreway.
Possibly the earliest example is the Emerald Necklace, which consists of a 1,100-acre (4.5 km2), or 445 hectare chain of parks linked by parkways (a broad, landscaped highway) and waterways in Boston and Brookline, Massachusetts, US. It gets its name from the way the planned chain appears to hang from the "neck" of the Boston peninsula. This linear system of parks was designed by Frederick Law Olmsted to connect Boston Common and Public Garden (1837) to Franklin Park, known as the "great country park." The project began around 1878 with the effort to clean up and control the marshy area which became the Back Bay and the Fens. In 1880, Olmsted proposed that the Muddy River, be included in the park plan. The current was dredged into a winding stream and directed into the Charles River. Olmsted's vision of a linear park of walking paths along a gentle stream connecting numerous small ponds was complete by the turn of the century but for a never completed section to Boston Harbor. However, the subsequent development of the automobile severely disrupted the original concept.