Port Sanilac Light, a United States Coast Guard lighthouse on Lake Huron near Port Sanilac, was established in 1886 to help close a dangerous unlit stretch of shoreline between Fort Gratiot Light and Pointe aux Barques Light, where shallow water and sandbanks threatened navigation. Still active and automated, it is known for its rare octagon-hourglass brick design by Captain Charles E. L. B. Davis, shaped partly by limited funding. The tower retains its original fourth-order Fresnel lens, one of few still operating in the United States. Listed on the National Register of Historic Places in 1984, the station remains architecturally distinctive and visually iconic.