In 1897, during the zenith of the shipping industry on the Great Lakes, a navigation light was put into service on the north-easterly point of Flowerpot Island. The light was to mark the main channel through the treacherous reefs and islands of the Tobermory Archipelago. That summer, a square wooden keepers cottage with a wooden tower for the light was erected atop Castle Bluff at a cost of $1,137. From a height of 33 meters (88ft.) above the water, the fixed white dipodic light was visible for 22.4 km (14 miles). Donald Smith, the first lightkeeper to be stationed here was paid $300. a season.

The original lighthouse building was burned and pushed from the cliff in 1969 after being replaced by the steel tower still at the site. The fog plant, which was decommissioned in 1995, now stands where the original lighthouse once stood.

Costing a total of $4,410.65, a building which housed the fog alarm machinery was established at the cliff site in 1909, replacing less effective bells and hand horns. This building was also destroyed in 1969. The observation deck occupies the site where the original fog building once stood.

The two-storey lighthouse keeper’s dwelling was built in 1901 at a cost of $1,396.93, on 24.37 acres of property that was purchased in 1900 from the Department of Indian Affairs at a cost of $8.64. The one-storey dwelling was built in 1959 at a cost of $18,000. Prior to its building, the assistant lightkeeper lived at the lighthouse on the cliff. The boathouse/workshop was erected in 1963.

Beside the boathouse are the remains