Reviewing the development of the public facilities policy in the Tainan city, the guide plan “City Renovation Plan” made by the Japanese colonial period has been applied for more than half century until now. Most public facilities are not aging-friendly because they were set in the surroundings of the administration buildings and become old and inaccessible now. Considered the declined mobility of the elderly people so that they are used to acting nearby their house, we find that the solution might be the usable open space in the community which is around users. In the viewpoint of the participative environmental planning, we have practiced in the “Yin-Tong community” for more than 4 years by establishing the relationship with the leader; the residents; the merchants in the community and by holding events for different purposes to reuse the abandoned places. As a result, this study found the operating mechanism and the ways to develop the accessible places for the elderly by reusing the abandoned open space in the community. Furthermore, the reusing also supplies aging in place and preserves the urban historical context instead of reconstructing the new facilities.