The LakeMaster® Pro Maps Michigan card contains shorelines for 18,500 lakes, bays, rivers and ponds, including Lake Michigan, Lake St. Clair, Green Bay, and portions of Lake Huron and Lake Erie. 820 of these are named and contain bathymetry. 700 inland lakes are within the borders of Michigan, with 49 of those being super high-definition, surveyed lakes with 1-to-3' depth contours! Also includes coverage of 96 additional lakes in the adjacent states of Illinois, Indiana, Ohio and Wisconsin.