Scow Schooners are an important yet largely unstudied vessel type that operated on the North American Great Lakes. At their zenith in the later 19th century scow schooners worked between the many small harbours and the larger nexus ports such as Chicago, Detroit, and Milwaukee. These vessels are virtually undocumented either historically or archaeologically. A project by East Carolina University's Maritime Studies Program and the State Historical Society of Wisconsin in 2001 documented the wrecked scow schooner Dan Hayes, revealing much information concerning this vessel class and the limestone industry in which it was employed. Although an ordinary scow schooner, its construction techniques are surprising, showing evidence of prefabrication. The bottom of the ship was apparently built inverted and flipped over before sides and bow were added, the first evidence that inverted construction could be accomplished with such large vessels.