SS Lansdowne was a railroad car ferry built in 1884 by the Wyandotte Shipyard of the Detroit Dry Dock Company. It was used from 1884 until 1956 between Detroit, Michigan, and Windsor, Ontario, across the Detroit River, although there are reports of its sporadic use until the early 1970s. At the time of its construction it was the longest ship on the Great Lakes at 312 feet (95 m).