The Fort Gratiot Lighthouse is the oldest operating lighthouse in the Great Lakes and was established in 1825, rebuilt in 1829, and expanded in 1861. This lighthouse was the first on Lake Huron and is the oldest surviving lighthouse in Michigan. The original tower was located approximately where the first Blue Water Bridge stands, which was not the best location. Partly due to a poor design and construction, this tower collapsed into the river during a severe storm in 1828. A new lighthouse was built north of the military fort in 1829 with a 65-foot tower. This new location helped keep watch over Lake Huron at the entrance to the St. Clair River and made it easier for ships to spot as they entered the rapids at the head of the St.Clair River. In the early 1860s, the tower was extended to its present height of 86 feet. The light stands above the lake level in a conical stone tower, overlaid with red brick that has been painted white. The keeper's cottage and fog whistle house are red.

Today, a Coast Guard station and the Fort Gratiot Lighthouse watch over one of the busiest waterways in the world. The Fort Gratiot Light Station is one of the few operating lighthouses that allows visitors to climb the tower and even step out onto the catwalk for a breathtaking view! Tower climbs and tours are available during business hours, weather permitting. From the tower, visitors may see the Blue Water Bridge, the mouth of the St. Clair River to the south, Lake Huron to the north, and Point Edward, Ontario further north.