The Impact of Housing Choice Vouchers on Health and Housing Outcomes - Increasing population levels of daily physical activity has assumed considerable public health significance in the past three decades, and recent efforts have expanded from targeting individual behavior change toward addressing environmental risk conditions that affect everyone within a community. Indeed, the built environment and urban design are now recognized as primary drivers of achieving an active and healthy lifestyle. Unfortunately, the distribution of these health-promoting environmental resources is not uniform, and people living in low-resource areas (urban and rural) bear a disproportionately higher burden of risk conditions and lifestyle-related chronic diseases, compared with their more affluent counterparts. This may be especially so for older people who have lived with adverse environmental risk conditions since childhood. Policy, Systems, and Environmental (PSE) strategies for promoting physical activity and other healthy behaviors are gaining momentum within the public health arena. The PSE framework comprises strategies for change that are both multi-sectoral and multi-level. Moreover, since they are directed toward the entire community, they are more maintainable and can address differences in opportunities and outcomes better than interventions targeted to the individual. One the other hand, PSE intervention strategies can be very expensive and require considerably more time to enact within communities. Thus, it becomes advantageous to identify naturally-occurring “interventions” (i.e., natural experiments) for which their impact on population behavior and health can be determined over time. The 11th Street Bridge Park Project (planned to break ground in late 2025 and open in 2027) offers an elegant strategy for accomplishing this, as it will connect one of the more affluent wards in DC (Ward 6) with the least affluent ward (Ward 8). We will examine the impact of this Bridge Park on longitudinal changes in the built environment itself, as well as in physical activity patterns and dietary choices within the areas directly affected by it. Specific Aims: 1) To determine the impact of the 11th Street Bridge Park Project on the built environments of Wards 6 and 8 that are within the sampling area (1-mile radius) surrounding the new park; 2) To determine the influence of this Project on spacio-behavioral characteristics of the park itself, as well as of the sampling areas of Wards 6 and 8 surrounding the park; and 3) To determine the impact of the 11th Street Bridge Park Project on individual- and family-level lifestyle behavior changes, as well as on perceptions of neighborhood safety, social connectedness, and food security using an intergenerational approach.