This oared galley propelled the classical Greek city states, and Athens in particular, into a naval power. The trireme (trieres in Greek) was named because the oarsmen were stationed at 3 levels, allowing more men to fit on a smaller ship. A standard trireme was about 120 ft long, and manned by over 150 oarsmen. The ships could cover about 180 nautical miles at a constant speed of 7.5 knots. They also had square sails, which could not always be used on the temperamental Mediterranean Sea. During the wars with Persia, Athens alone commanded over 200 of these ships.