Navis lusoria

A navis lusoria (from Latin, meaning dancing/playful ship, plural naves lusoriae) is a type of a small military vessel of the late Roman Empire that served as a troop transport. It was powered by about thirty soldier-oarsmen and an auxiliary sail. Nimble, graceful, and of shallow draft, such a vessel was used on northern rivers close to the Limes Germanicus, the Germanic border, and thus saw service on the Rhine and the Danube. The Roman historian Ammianus Marcellinus mentioned the navis lusoria in his writings, but not much about it could be learned until the discovery of such boats at Mainz, Germany in 1981–82.

In November 1981, during excavation in the course of a construction of a Hilton Hotel at Mainz, wooden remains were found and identified as parts of an old ship. Before construction resumed three months later, the site yielded remnants of five ships that were dated to the 4th century using dendrochronology. The wrecks were measured, taken apart, and, in 1992, brought to the Museum of Ancient Seafaring (German: Museum für Antike Schifffahrt) of the Romano-Germanic Central Museum (Römisch-Germanisches Zentralmuseum) for further preservation and study.

Scientifically the wrecks were termed Mainz 1 through Mainz 5 and generally referred to as the Mainzer Römerschiffe, the Mainz Roman ships. They were identified as military vessels that belonged to the Roman flotilla in Germania, the Classis Germanica. The vessels could be classified into two types, namely small troop transports (Mainz 1, 2, 4, 5) termed navis lusoria and a patrol vessel (Mainz 3). The lusoria is narrower than the navis actuaria, an earlier and wider type of Roman cargo vessel.

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