Since the 1980s, significant investments have been made in urban rail transit across the United States, particularly using light rail technology. Most of these light rail systems have been built in Sunbelt cities which no longer had legacy rail systems. As a result, they were constructed using a building blocks approach, being funded corridor by corridor. Most research, however, on urban rail performance has taken place at the system-wide level, leaving a significant gap at the level of the transit corridor. This research examined nineteen urban rail corridors in Denver, Salt Lake City, and Portland. A performance score was constructed for each corridor based upon ridership per mile, ridership growth, capital costs, and the cost of ongoing operations. These scores were then compared with a constructed profile of each corridor studied, which included aspects including but not limited to population and job density, median income, park and ride spaces, bus connections available, walkability, and headways between trains. Corridors in each city ranked high and low, with no city emerging as a clear frontrunner. Headways, population density, and percentage renter occupied housing units were found to have a statistically significant relationship with high corridor performance, largely in line with previous studies. Qualitative data gathered from this research suggest that partnerships with municipalities, communities, and businesses also played a crucial role in the development of successful urban rail corridors.