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Marine navigation -- Follow the links to dive deeper.

Links in the text below direct users to mostly Wikipedia entries.  Wikipedia should be used as a starting point for deeper dives into various topics. Readers are encouraged to visit links on the Wikipedia pages that lead to more detailed and authoritative content.


The USCG Navigation Center provides services to enhance the safety, security, and efficiency of U.S. waterways, and respond to the needs of civil Global Positioning System (GPS) users. These services include:

• Disseminating navigation information through 24/7 operations center and NAVCEN website

• Operating the Nationwide Automatic Identification System (NAIS)

• Serving as the primary U.S. government interface with GPS users (except aviation and DOD)

• Receiving and coordinating investigation of GPS outage reports • Operating the Nationwide Differential GPS (DGPS) System

• Operating the Long Range Identification and Tracking (LRIT) business helpdesk

• Publishing Notices to Mariners and the Light List

• Managing the US Aids to Navigation Information Management System

• Managing electronic charting portfolios for U.S. Coast Guard units


U.S. Chart No. 1 presents two types of symbology used for marine navigation – the symbols used on paper nautical charts (and their digital raster image equivalents) and the corresponding symbols used to portray Electronic Navigational Chart (ENC) data on Electronic Chart Display and Information Systems (ECDIS).

This is your best source for learning what all the symbols on your nav charts mean.  It is good to have a copy of Chart 1 onboard if you plan to do any cruising outside of your home waters.


The United States Coast Pilot is published by the National Ocean Service (NOS), National  Oceanic and Atmospheric Administration (NOAA), pursuant to the Act of 6 August 1947 (33 U.S.C. 883a and b), and the Act of 22 October 1968

The Coast Pilot supplements the navigational information shown on NOAA nautical charts. The Coast Pilot is continually updated and maintained from inspections conducted by NOAA survey vessels and fi eld parties, corrections published in Notices to Mariners, information from other Federal agencies, State and local governments, maritime and pilots’ associations, port  authorities, and concerned mariners.

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