Rail speed limits in the United States

Parts of this article (those related to track examples) need to be updated. Please help update this article to reflect recent events or newly available information. (January 2015)

Rail speed limits in the United States are regulated by the Federal Railroad Administration. Railroads also implement their own limits and enforce speed limits. Speed restrictions are based on a number of factors including curvature, signaling, track condition, and the presence of grade crossings. Like road speed limits in the United States, speed limits for tracks and trains are measured in miles per hour (mph).