Pottawatomie Light

Pottawatomie Light, also known as Rock Island Light, is a lighthouse standing on Rock Island in Door County, Wisconsin, within Rock Island State Park on Lake Michigan. It holds the distinction of being the oldest light station in Wisconsin and on Lake Michigan, with its first beacon lit in 1836.

The tower is a square, limestone structure that is integral with its keeper’s house, rising 41 ft from a stone foundation. Its natural stone walls are topped by a black lantern. The light’s focal plane sits 159 ft above the water, its Fresnel lens projects a white flash every 4 seconds (Fl W 4s) and reaches a range of 7 nmi. Dense foliage obscures the beam from 275° to 020°.

The original 1836 station consisted of a 1½‑story house and a 30‑ft detached tower, but poor construction led to replacement by the present limestone lighthouse in 1858. The early tower and dwelling were later demolished. Civilian keepers tended the light from its start until it was automated, after which it remained an active aid until 1988, when a modern skeletal tower took over.

Deactivated in 1988, the historic tower is no longer an operational beacon. It remains a preserved landmark within Rock Island State Park and is listed on the National Register of Historic Places.

Light and tower

It was first lit in 1836. It was automated in 1946.