Poe Reef is a lighthouse located at the east end of South Channel between Bois Blanc Island and the mainland of the Lower Peninsula, about 6 miles east of Cheboygan, Michigan.
Poe Reef has historically caused problems for shipping. Powered vessels heading west to Lake Michigan generally use South Channel, which is approximately three nautical miles wide, but Poe Reef sits close to the middle of the channel, and to the north of it the water is too shallow for lake freighters.
Many attempts were made to position a lightship here but it was difficult. Four different lightships served beginning in 1893: Lightships Nos. 62, 59, 96, and No. 99.
The Poe Reef Light was an extension of the effort—beginning in 1870 through 1910—where engineers began to build lights on isolated islands, reefs, and shoals that were significant navigational hazards. Until that time, Light ships were the only practical way to mark the hazards, but were dangerous for the sailors who manned them, and difficult to maintain. "Worse, regardless of the type of anchors used lightships could be blown off their expected location in severe storms, making them a potential liability in the worst weather when captains would depend on the charted location of these lights to measure their own ship's distance from dangerous rocks." See, United States lightship Huron (LV-103).
The Poe Reef is one of several that mark the passage through the South Channel. The other major light is Fourteen Foot Shoal Light. The decision was made by the United States Lighthouse Service in 1926 to construct a permanent light here. The Poe Reef Light was completed in 1928.
The Poe Reef Light is part of what became a complex of 14 reef lights in Michigan waters, which was intended to help ships navigate through and around the shoals and hazards of the Great Lakes. It is also "part of a series of a significant offshore light construction projects being undertaken in the Straits area in the late 1920s." The same crew that built this light also built St. Martin's Light from almost the same plan.
The Poe Reef lighthouse marks the north side of the South Channel of the Straits of Mackinac, while the Fourteen Foot Shoal Light marks the south side of the channel. Most sailing vessels had used the channel on the north side of Bois Blanc Island, but the growth of steamboat traffic increased use of the South Channel.
The Poe Reef Light shares designs with a twin, Martin Reef Light (all white, however, and with different windows in the fourth floor), which was built in 1927 by the same construction crew. The Poe lighthouse was originally painted all white, which sometimes confused mariners because they shared colors and a common structural design. Thus, a decision was made to paint Poe in contrasting bands.
The Poe Reef station was designed so that the onsite crew could also remotely operate the Fourteen Foot Shoal Light. Subsequently, both lights have been fully automated. The Poe Reef diaphone fog horn is still in current service.
In 2005, the Poe Reef Light lighthouse was listed on the National Register of Historic Places and the parallel state inventory of historic sites.