Background: The Geriatric Unit of the University of Palermo developed the “Passiata Day” model, a green exercise intervention consisting of a one-hour walk, once/week, in a city park. The purpose of this study was to assess body balance in older people who walked regularly compared to sedentary people. Methods: 106 older people (75 women and 31 men; mean age: 72.3 ± 8.2 years) without fall history were invited to participate voluntarily in this natural environment walking program. After six months, both the participants who had taken part regularly in the walk (i.e., the physical activity group (PAG; n = 72; 54 women and 18 men; mean age: 70.7 ± 7.2 years)), and who had not accepted to be included in the outdoor walking program (i.e., the sedentary group (SG; n = 34; 21 women and 13 men; mean age: 75.5 ± 9.4 years)), performed a stabilometric test with open eyes (OE) and with closed eyes (CE). Results: Our preliminary results showed significant differences between groups on the ellipse sway area both in the OE (p < 0.05) and in CE condition (p < 0.01). Moreover, we found a significant difference on sway along the frontal plane both in the OE (p < 0.05) and in the CE condition (p < 0.01), and on sway along the sagittal plane for the test with CE (p < 0.01). Conclusion: Based on our preliminary findings, we suggest that walking regularly in an outdoor setting could lead to a greater body balance in older people and could be recommended by geriatricians for preventing the risk of falls. The next step will be to investigate the effect of an experimental outdoor walking program structured in terms of intensity, frequency and volume.