This study presents a targeted analysis of qualitative data under a parent study integrating the World Health Organization's Age-Friendly Cities, Healthy Cities, and sustainable cities policy frameworks. To focus on implications for mental health promotion and nursing, data-analysis was performed mobilizing the Canada Health Act (CHA) as theoretical framework. Using data from 22 semi-structured interviews with community members (n = 17) and global policy stakeholders (n = 5), this analysis reveals how transportation may be a central factor through which environmental design influences accessibility to health care services, including mental healthcare. Thematic analysis revealed three interrelated factors-transportation cost, travel time, and travel risk-as central to understanding how city planning intersects with preexisting social marginalization to confound psychosocial outcomes. When viewed through the CHA's framework, transportation barriers effectively render public healthcare systems functionally inaccessible for many, particularly individuals facing compounded challenges related to socioeconomic status, age, disability, and limited mobility. Overall, the sub-study suggests that the design of one's physical environment can profoundly shape both access to care and one's perceived ability to find respite from, cope with, or resolve mental health stressors. Conceptualizations of the "world," in alignment with other mental health research, illuminate the ways in which transportation infrastructure and urban planning either expand or contract the scope of lived experience and autonomy to impact daily mental wellbeing. A preliminary framework of mental health nursing understood in terms of environmental and transportation planning concludes the study.