Galleys continued to be widely used in the Mediterranean in the second half of the Middle Ages. Some of them were slightly larger than the earlier versions, as shown by studies of the handful of these vessels that archaeologists have found partially intact. Noteworthy was a galley constructed for England’s King Henry V, the remains of which were found in an English river in 1933. In its prime, the ship was 125 feet (38 m) long and 50 feet (15 m) wide at the beam (midpoint of its length). h e i nal medieval centuries were also notable for ship designers’ introduction of several crucial technical advances. One, which came in the early 1400s, was the addition of a second mast bearing one or two extra sails. Another new mast, the bowsprit, projecting forward from the bow (front) of the ship, added still more sails, increasing the vessel’s propulsive power as well as its speed. h ese developments rapidly eliminated the need for oars. h e result was the emergence of true sailing ships, often called roundships. h ey had higher, wider hulls than galleys, making them more robust and stable. h e extra height was most pronounced in the stern (rear), which featured a so-called “castle,” a big cabin, or cluster of small ones, topped by a deck that towered over the rest of the ship. h e castle of ered a strategic military advantage because archers, slingers, and even small onboard catapults could be stationed there. Its added height increased the chances that their missiles would strike nearby enemy ships.