Sandusky (səndŭs´kē, săn–), industrial city (1990 pop. 26,764), seat of Erie co., N central Ohio, a port of entry on Sandusky Bay of Lake Erie; inc. 1824. Its natural harbor has coal-loading docks, and sand, gravel, and salt are also shipped. Sandusky has a fishing industry and many assorted manufactures. It has been a tourist center since the 1880s. Nearby are Cedar Point, a summer resort; Kelleys Island and numerous other small islands; Blue Hole Spring; Crystal Rock Caves; and Marblehead Peninsula.

Sandusky, river, c.120 mi (190 km) long, rising in N Ohio and flowing W through Bucyrus, then N past Tiffin to Sandusky Bay, an arm of Lake Erie. This landlocked bay, 18 mi (29 km) long, is one of the best harbors on the lake.