What is the "sense of green gain" around us and the "sense of ecological happiness" at home? The Yuandu City Wall Ruins Park in Beijing, which has just "torn down the walls and turned green", made the residents come to appreciate deeply: "Without the gate area, let alone the fence, people unknowingly walked into the park." "The park is just below the residents' buildings, so you don't have to go far." Since September this year, 52 urban parks in Beijing, including Chaoyang Park and Yuandu City Wall Ruins Park, will have completed "tearing down walls to reveal green", winning praise both online and offline. Behind the "demolition" is actually standing. Explore a new mode of open management of urban parks, make parks truly integrated into the city, make urban green heart and urban life organically integrated, and make residents more comfortable and convenient to enjoy the achievements of ecological construction. A long green footpath carries the happiness of people's livelihood, and a small pocket park carries many joys. The park is the "green lung" of the city and the "leisure paradise" of residents, which is closely related to the happiness index of people's life. The opening of the park has broken the traditional closed management mode of the park, made the park move from closed to open, more user-friendly and beneficial to the people, and effectively improved people's sense of ecological gain and happiness. This is the constant deepening and refinement of the "people-oriented" concept of urban management in the practice of ecological civilization construction. There is no distance between park green space and residents' life, and mountains, rivers, trees and urban landscape blend together, which has become a new trend in urban construction around the world. "The environment is the people's livelihood". All parts of the country continue to promote the construction of "tearing down walls to see through green", "pushing doors to see green", "leaving blank to increase green", and so on. The picture of parks and cities with urban green integration and harmonious people and cities is slowly unfolding. The quality of life and happiness index of residents are constantly improving in the positive and promising improvement and enrichment of the ecological environment. Not only is it "tearing down walls to see through green", from pocket parks to country parks, open parks are springing up to respond to public opinion and emerge at the historic moment. For example, the Notice on Promoting the Construction of "Pocket Parks" issued by the Ministry of Housing and Urban Rural Development in August this year proposed to promote the construction of "pocket parks" in at least 1000 cities nationwide by 2022, and requested that the needs of the surrounding people be fully considered, activity venues be increased, and the requirements of aging and childlike adaptation be implemented. For another example, Beijing has built a number of new country parks, most of which are open without walls. Since this year, Beijing has also scientifically optimized fences to promote the connectivity of ecosystems, urban greenways and park trails, and ecological landscape corridors, so that more parks can truly integrate with the city. The implementation of open park management is an effective way to enhance people's sense of ecological gain and happiness. "A good ecological environment is the most inclusive livelihood", and parks are one of the well-being around residents. The park is an important infrastructure of urban ecological construction and a component of ecological civilization construction. It is a general trend and popular sentiment to return green to the people, upgrade "parks in cities" to "cities in parks", and vigorously promote the construction of parks and cities. The creation of a park city is not a simple model of "park+city". It should be organic with the direction and purpose of making residents' lives better