Two Harbors Light
The Two Harbors Light is the oldest operating lighthouse in the US state of Minnesota. Overlooking Lake Superior's Agate Bay, the lighthouse is located in Two Harbors, Minnesota. The construction of the lighthouse began in 1891 and was completed the following year, with the light being lit for the first time on April 14, 1892. The first Two Harbors keeper was Charles Lederle and there were normally three keepers assigned to make sure the light was lit every day. The Lighthouse was built to provide safe passage into the Agate Bay Harbor during the early 20th  century, as Two Harbors was a major shipping point for the iron ore of the Mesabi Range. The tower is made of red brick and the head keeper's residence is attached; it towers from the lake level to the top and is squared. The walls of the tower were built to be three bricks thick and the walls where the tower and house meet are a full five bricks thick. This was for the safety of the keeper's family. The light has a total of six structures: a lighthouse tower with attached keeper's quarters, an assistant keeper 's house, a fog signal building, an oil house, a skiff house, and a garage. The lighthouse was originally equipped with a fourth order Fresnel lens. The lighthouse is a twin of the Round Island Light in Michigan. In 1969 the Coast Guard removed the Fresnel lens and replaced it with a DCB-224 aerobeacon which is still used today. The light shines an average of . The original lens was loaned by the US Coast Guard to the National Museum of the Great Lakes. In early 2015, the lens was moved back to Two Harbors and is now on is now  on display in the dining room of the Keeper's Quarters. The Lake County Historical Society began to provide tours of the Lighthouse Station in 1988 when it was granted a lease by the U.S. Coast Guard. In 1999 ownership was transferred to the Lake County Historical Society and the Society assumed responsibility for the operation of the light in 2001. While the lighthouse is still on the Light List as active, it is listed as a private aid to navigation and is no longer maintained by the Coast Guard. Three of the lighthouse station's buildings are open for  visitors to tour: Also on the site is the Pilothouse from the Frontenac ore boat, which contains an exhibit on its history and shipwrecks. The lighthouse was listed on the National Register of Historic Places on July 19, 1984 as Two Harbors Light Station, reference number 84001483.