People with physical disabilities constitute the largest minoritized group in the U.S. and world, and are susceptible to physical inactivity which elicits many negative health effects. Inactivity is exacerbated by a paucity of opportunities to participate in structured physical activity (UPA) like adapted fitness centers. In response, the present study sought to evaluate perceived accessibility of unstructured physical activity in eight urban and rural locations between the U.S. and Scandinavia. A mixed-methods questionnaire was developed to investigate four subdomains within perceived accessibility: regional climatology, the built environment, public transportation, and psychosocial interactions. Findings were situated within the Disablement Process Model and Socioecological Participation Model of People with Disabilities. Facilitators increasing likelihood of physical activity engagement included flat terrain, compatible footpath materials, accessible public transportation, and inclusion. Barriers modulating participation included severe gradients, narrow or nonexistent footpaths, inaccessible public transportation, and dependency. U.S. urban contexts were deemed most facilitative of physical activity participation. Thus, wheelchair users are equipped with content knowledge to effectively evaluate a region for adequate physical activity accessibility, thereby encouraging the notion that activity opportunities should be made accessible such that all can independently lead healthy lives.