Urban parks in city centers are often assessed by residential proximity, but visits in districts with mixed land uses also occur between work, shopping, services, and other daily activities. A nearby park may remain difficult to use when its entrances and internal paths do not align with the routes people take to reach it. This study presents Park-BIND (Park Boundary-Opening Identification and Network-Based Decision Model). It connects the activities before and after a park visit with complete walking routes, candidate feasibility, exhaustive optimization of opening sets, and space syntax analysis. Applied to two parks in the central area of Shanghai, the model evaluated and reviewed entrances and opening options suited to each site. Minimum opening sets designed to achieve 80% of the feasible route benefit (S80) captured 85.40% in Xujiahui Park and 82.42% in Xiangyang Park. High overall efficiency did not ensure balanced benefits. Balanced solutions raised the activity context receiving the least benefit above 90% of its feasible benefit in both parks. The opening scenarios also changed Integration, Choice concentration, and exposure to structurally important paths. These indicators describe potential movement patterns, not observed pedestrian flows or congestion. The findings support a phased strategy: begin with a small set of feasible and effective connections, add openings where needed to serve activity contexts more evenly, and reserve options with higher benefits or conditional feasibility for later action. Park access should therefore connect routes from city streets through public entrances to usable paths inside the park, rather than rely on proximity or entrance numbers alone.