This study focuses on the preservation of the Bismarck-Mandan rail bridge and surrounding 200-acre site as a catalyst to transform the waterfront of North Dakota’s capital city into a 21st-Century urban park. Announced by the National Historic Trust for Historical Places, the iconic community structure has been listed as one of “America’s 11 most Most Endangered Historic Places” in 2019. With the backing of the Historic Trust, Preservation of North Dakota, community members, and the non-profit group, Friends of the Rail Bridge, the historic truss bridge has gained traction to be repurposed as a pedestrian bridge linking the parks and open spaces of the two cities. Much like the Brooklyn Bridge site, which the rail bridge predates, the city had turned its back on the river. Utilizing a comparative case study methodology to compare successful traits of transformative waterfronts, particularly in an urban context, this study resulted in a best-practices matrix to inform the urban park programming and design. This project expands on the role of a separate entity tasked with the re-purposing, operation, and maintenance of the bridge to include creating an adjacent park suitable enough to become a mixed-use destination and a city-shaping gateway to the West.