Open space lands are provided by a variety of entities from private individuals to the federal government and these entities make management decisions based on a very broad range of priorities. The net benefits of additional open space depend on the number, quality, and composition of existing open space in the vicinity. In areas where open space is abundant and there is a significant proportion that is federally owned, the net benefits are not well understood. In this study, the marginal willingness to pay for proximity to public open space is estimated using the hedonic property method and home sales transactions in 2007 for El Paso County Colorado, a location that boasts of having over 150,000 acres of open space. Results from a generalized spatial two-stage least squares regression indicate that homes in close proximity to open space provided locally by city, county, and state governments sell for a premium, but larger premiums are associated with proximity to the Pike National Forest and Cheyenne Mountain Air Force Station likely at least partially due to the natural amenities of the Rocky Mountains. In contrast, proximity to Fort Carson Army Installation is found to negatively affect house sales prices likely due to undesirable activities that occur on and around the installation. As for the other area of federal lands, proximity to the U.S. Air Force Academy and to Peterson Air Force Base was found to negatively affect house prices; however, these effects were not statistically significant.