Coastal Survey maps are certainly a specialized record set. But if you had ancestors who lived or worked around the water, they may yield important information for you. This collection for the Office of Coast Survey offers maps for sale, but you can search for them and see the results without fee.
The landing page gives you a search box where you can search by title, type of map, state, year, or chart. The most interesting and fun search, however, is using the link to a map-based search page. That link is just above the search box. It gives you a map of the US (you can pan to any place in the world) that you can zoom in on by double clicking. When you find a place of interest, you can select a point on the map to get a list of applicable maps to review.
Although we are dealing with coastal survey maps, click on any plane on the maps and you will be offered a list of maps. That is because the survey deals with both fresh and salt water areas.
Office of Coast Survey Historical Map & Chart Image Catalog:
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