Nautical chart features contained within a NOAA ENC provide a detailed representation of the U.S. coastal and marine environment. The data, updated weekly, is organized using S-57 object classes. Features in a single NOAA ENC are limited in that they only represent the geographic region that is depicted in that particular NOAA ENC cell. By aggregating nautical features from all NOAA ENC in the creation of GIS data, a continuous depiction of the U.S. coastal and marine environment is achieved.