The Rock Harbor Lighthouse is a light station located in Rock Harbor on Isle Royale National Park, Michigan. It was listed on the National Register of Historic Places in 1977.
The Rock Harbor Lighthouse is a 50-foot-tall (15 m) cylindrical tower with a 16-foot-diameter (4.9 m) base, constructed of randomly placed stone and brick, capped with an octagonal beacon with a copper roof. A one-and-a-half-story keeper's house with gabled roof is connected to the tower on one end.
In 1852, due to the increase in shipping in Lake Superior, it was recommended that a new light be constructed on Isle Royale; the next year, Congress appropriated $5,000 to construct a light at Rock Harbor. Construction began in 1855, and was completed in 1856. The Rock Island Light was the first lighthouse constructed on Isle Royale. The first keeper arrived at the station on October 24, 1856, and the lighthouse went into operation a short time later.