A dromon (from Greek δρόμων, dromōn, "runner") was a type of galley and the most important warship of the Byzantine navy from the 5th to 12th centuries AD, when they were succeeded by Italian-style galleys. It was developed from the ancient liburnian, which was the mainstay of the Roman navy during the Empire. Middle English dromond and Old French dromont are derived from the dromon, and described any particularly large medieval ship. Evolution and features The appearance and evolution of medieval warships is a matter of debate and conjecture; until recently, no remains of an oared warship from either ancient or early medieval times had been found and information had to be gathered by analyzing literary evidence, crude artistic depictions and the remains of a few merchant vessels (such as the 7th-century Pantano Longarini wreck from Sicily, the 7th-century Yassi Ada ship and the 11th-century Serçe Limanı wreck). Only in 2005–2006 did archaeological digs for the Marmaray project in the Harbor of Theodosius (modern Yenikapi) uncover the remains of over 36 Byzantine ships from the 6th to 10th centuries, including four light galleys of the galea type. The accepted view is that the main developments which differentiated the early dromons from the liburnians and that henceforth characterized Mediterranean galleys, were the adoption of a full deck (katastrōma), the abandonment of the rams on the bow in favor of an above-water spur and the gradual introduction of lateen sails. The reasons for the abandonment of the ram (, ) are unclear. Depictions of upward-pointing beaks in the 4th-century Vatican Vergil manuscript may well illustrate that the ram had already been replaced by a spur in late-Roman galleys. Byzantinists John Pryor and Elizabeth Jeffreys argue that the purpose of the spur was to allow the dromon to ride up on an enemy's oars and crush them, destroying its propulsion, and point out that one of the medieval Latin terms for spur, "calcar," is derived from the verb "to trample". One possibility is that the change occurred because of the gradual evolution of the ancient shell-first mortise and tenon hull construction method, against which rams had been designed, into the skeleton-first method, which produced a stronger and more flexible hull, less susceptible to ramming. By the early 7th century, the ram's original function had been forgotten, if we judge by Isidore of Seville's comments that they were used to protect against collision with