[Edit this paragraph] The connotation of greenway Broadly speaking, "greenway" refers to all kinds of linear open spaces for connection, including community bicycle lanes to habitat corridors that guide the seasonal migration of wild animals; From the waterfront of the city to the riverside tree-lined path far away from the city. However, the connotation of "greenway" is very wide, and it will have different meanings under different environments and conditions. So the definition of this concept will always have certain limitations. Here, we can quote the definition given by Charles Little in his classic book Greenway for American: Greenway is a linear open space along natural corridors such as river banks, valleys and ridge lines, or along artificial corridors such as abandoned railway lines, ditches and scenic lanes for entertainment activities, including all natural and artificial landscape lines for pedestrians and cyclists. It is an open space link connecting parks, nature reserves, scenic spots, historical sites and other high-density residential areas. At the local level, it refers to some strip or linear parks, which are considered as park roads or green spaces. [1] Subsequently, based on literature review and combined with American experience, Ahern defined greenway as a land network composed of linear elements, which was planned, designed and managed for various purposes (including ecology, leisure, culture, aesthetics and other purposes consistent with sustainable land use). The definition emphasizes five points: ① the spatial structure of greenway is linear; ② Connection is the most important feature of greenway; ③ Greenways are multifunctional, including ecological, cultural, social and aesthetic functions; ④ Greenways are sustainable, which is the balance between nature protection and economic development; ⑤ Greenway is a specific spatial strategy of a complete linear system. [2][ Edit this paragraph] Greenway Characteristic Greenway is an advanced concept from developed countries in Europe and America, and there is no complete experience to follow in China. Greenways are mainly composed of non-motor vehicle trails such as pedestrian walkways and bicycle lanes, recreational facilities such as parking lots, cruise terminals, car rental shops, rest stops, tourist shops and specialty shops, and green buffer belts with a certain width. According to the needs, a certain range of ecologically sensitive areas or agricultural production land can be designated outside the greenway as urban ecological corridors or group isolation zones. Greenway network is composed of several regional greenways, urban greenways and community greenways. It is an important part of urban and rural and regional ecological network system, integrating environmental protection, sports, leisure, tourism and other functions, and is an effective carrier that perfectly combines ecological protection, improving people's livelihood and developing economy. Greenway construction basically does not need to occupy the index of construction land, and has the characteristics of less investment and quick results, which meets the development requirements of building a low-carbon city and is also one of the effective measures to expand domestic demand, stimulate consumption and promote economic development. It can also comprehensively improve the quality of life of urban and rural residents, improve urban functions, strengthen local features and enhance development taste. [3][ Edit this paragraph] Greenway development stage1(1867 ~1900): Most documents of early greenway planning believe that the origin of greenway thought can be traced back to Frederick Law Olmsted and his famous Boston Park system completed in1867. The plan connects Franklin Park with Arnold Park, Jamaica Park, Boston Garden and other green space systems. The green space system is 25 kilometers long, connecting Boston, Brooklyn and Cambridge, and connecting with the Charles River. Later, Charles Eliot expanded his idea and extended his green grid to the whole Boston metropolitan area, covering 600 kilometers and connecting five coastal rivers. The second stage (1900 ~ 1945): Landscape architects mainly include olmsted Brothers, Eliot 1I and Henry Wright who are engaged in greenway planning. The olmsted brothers completed the 64-kilometer Portland Square Ring in memory of Lewis and Clark, which was later extended to 225 kilometers by planners. Open space planning in Massachusetts completed by Eliot II. Henry Wright completed the green space and greenway planning in Radburn, New Jersey. At the same time, the National Park Service (NPs) has carried out a large number of park road planning practices, such as Blue Bridge Park Road. The third stage (1960s-1970s): Greenway planning under the influence of environmental protection movement. During the 1960s and 1970s, the environmental protection movement in the United States flourished, forming three greenway research centers and representative researchers. Philip (University of Wisconsin) surveyed the natural and cultural resources in Wisconsin, and found that most of the important resources were distributed on both sides of the river corridor, and completed the Wisconsin Heritage Trail Proposa 1. Macharg, an Iranian, wrote "Design with Nature", especially one chapter focused on the planning of river corridors. The Maitland research group led by UniversitV 0f Massachusetts paid more attention to quantitative research. The fourth stage (1980s-1990s): The Greenway Movement was named in 1980s, and the report of the American President's Committee on Outdoor Recreation emphasized the opportunities that the Greenway brought to residents to get close to nature. 1990, Littl first defined greenway. In North America, there are thousands of greenway planning practice projects at present, but the research work is seriously lagging behind, and most of them are limited to project summary. The fifth stage (1990s-present): Greenway has become an international movement, and the Greenway movement has flourished. There are several international, national and regional greenway projects in the world. In terms of theoretical research, a large number of research results have emerged, a large number of research monographs have been published, many academic conferences on greenways have been held, and doctoral theses on greenways have appeared. The network about greenways is also overwhelming. [2][ Edit this paragraph] Greenways can be divided into the following five types according to the different formation conditions and functions: (1) Urban river type (including other water bodies) This kind of greenway is very common, and it is usually established as part of the rehabilitation and development project of urban decay waterfront in the United States. (2) Entertainment type