The physiological impact of walking in nature was quantified via continuous heart rate variabil-ity (HRV), pre- and post-walk saliva cortisol measures, and self-reported mood and mindfulness scores for N=17 participants who walked “The Green Road” at Walter Reed National Military Medical Center in Bethesda, Maryland. For N=15 of the participants, HRV analysis revealed two main groups: group 1 individuals who had a 104% increase (mean) in root mean square standard deviation (RMSSD) and 47% increase (mean) in standard deviation of NN values (SDNN) indi-cating an overall reduction in physiological stress from walking the Green Road, and group 2 in-dividuals who had a decrease (mean) of 42% and 31% in these respective HRV metrics signaling an increase in physiological stresses. Post-walk self-reported scores for vigor and mood disturb-ance were more robust for the Green Road than for a comparable urban road corridor and showed that higher HRV during the walk was associated with improved overall mood. Saliva cortisol was lower after taking a walk for all participants and showed that walking the Green Road elicited a significantly larger reduction in cortisol of 53% on average when compared with 37% of walking along an urban road. It is also observed that the order in which individuals walked the green road, and urban road also impacted their cortisol response with those walking the urban road before the green showing a substantial reduction in cortisol, suggesting a possible attenuation effect of walking the green road first. These findings provide quantitative data demonstrating the stress-reducing effects of being in nature, thus supporting the health benefit value of providing access to nature more broadly in many settings.