This line shapefile includes Global Map data showing ferries on major roads in the United States and Puerto Rico. Ferries are ships that carry vehicles, passengers, and cargo across a body of water. The ferries shown in this map layer can be considered additions to or extensions of the major roads system of the United States. The transportation routes these ferries continue are identified. Train ferries are not included. The data are a modified version of the National Atlas of the United States 1:1,000,000-Scale Ferries of the United States. This is an update of the 2013 map layer. This layer is part of the 1997-2014 edition of the National Atlas of the United States.Global Map data are part of a cooperative effort among national mapping organizations around the world to produce and maintain a standard set of basic cartographic data that supports global investigations of natural and human-built environments. Participating nations prepare data using a common data structure and description to ensure compatibility and to tangibly promote the tenets of the Global Spatial Data Infrastructure. These data are intended for geographic display and analysis at the national level, and for large regional areas. The data should be displayed and analyzed at scales appropriate for 1:1,000,000-scale data. No responsibility is assumed by the National Atlas of the United States in the use of these data.