What are Nautical Charts?
A nautical chart is a map that depicts the configuration of the shoreline and seafloor. The nautical chart is essential for safe and economical navigation. Federal regulations require most commercial vessels to carry electronic or paper nautical charts while they transit U.S. waters. Since the mid-1830s, the U.S. Coast Survey has been the nation’s nautical chart maker. NOAA's Office of Coast Survey is still responsible for creating and maintaining all charts of U.S. coastal waters, the Great Lakes, and waters surrounding U.S. territories.
What can I learn using these maps?
Fortunately for the Keweenaw Time Traveler, Nautical charts of the Keweenaw include important details for towns and landmarks along the shoreline. Nautical charts provide water depths, locations of dangers to navigation, locations and characteristics of aids to navigation, anchorages, and other features. Aids to navigation often include points of reference from the shore, such as vegetation, farms, large industrial, commercial, and residential buildings, as well as navigational buoys and lighthouses. Looking at Nautical maps can give you a sense for how important Lake Superior and maritime navigation has always been for life in the Keweenaw.
Tips & Tools for Reading these maps
Map keys are present on most of the map overlays within the Explore App. The ‘dictionary’ that contains the complete symbology for United States nautical charts is U.S. Chart No. 1, prepared jointly by the Department of Commerce, the National Oceanic and Atmospheric Administration, the Department of Defense, and the National Geospatial-Intelligence Agency.