The article explores the relationship between the built environment and social capital, focusing on the impact of walkable neighborhoods on community involvement and health. It highlights that social networks and community engagement are positively associated with better physical and mental health. Social capital, defined as the trust and reciprocity fostered through social networks, is linked to various positive outcomes, including improved health, democratic functioning, crime prevention, and economic development. The study examines how neighborhood design affects social capital, particularly in Galway, Ireland, where a mix of traditional and modern neighborhood types exists. Traditional neighborhoods, characterized by mixed-use and pedestrian-oriented designs, are contrasted with modern, car-dependent suburbs. The research uses a survey to assess the walkability of neighborhoods and measures social capital through factors such as knowing neighbors, political participation, trust, and social engagement. The findings indicate that residents of walkable, mixed-use neighborhoods are more likely to have higher levels of social capital. Multivariate models show that neighborhood walkability is a significant predictor of social capital, with a higher walkability score associated with increased social capital. The study suggests that the built environment, specifically walkable, mixed-use neighborhoods, can enhance social capital and, by extension, improve public health. However, the trend towards car-dependent suburban development in many parts of the United States may negatively impact social capital and health. The article calls for policy changes to encourage the development of more walkable, mixed-use neighborhoods and for public awareness to shift towards valuing these environments.The article explores the relationship between the built environment and social capital, focusing on the impact of walkable neighborhoods on community involvement and health. It highlights that social networks and community engagement are positively associated with better physical and mental health. Social capital, defined as the trust and reciprocity fostered through social networks, is linked to various positive outcomes, including improved health, democratic functioning, crime prevention, and economic development. The study examines how neighborhood design affects social capital, particularly in Galway, Ireland, where a mix of traditional and modern neighborhood types exists. Traditional neighborhoods, characterized by mixed-use and pedestrian-oriented designs, are contrasted with modern, car-dependent suburbs. The research uses a survey to assess the walkability of neighborhoods and measures social capital through factors such as knowing neighbors, political participation, trust, and social engagement. The findings indicate that residents of walkable, mixed-use neighborhoods are more likely to have higher levels of social capital. Multivariate models show that neighborhood walkability is a significant predictor of social capital, with a higher walkability score associated with increased social capital. The study suggests that the built environment, specifically walkable, mixed-use neighborhoods, can enhance social capital and, by extension, improve public health. However, the trend towards car-dependent suburban development in many parts of the United States may negatively impact social capital and health. The article calls for policy changes to encourage the development of more walkable, mixed-use neighborhoods and for public awareness to shift towards valuing these environments.