The Roman Navy (Latin: Classis, lit. "fleet") not only aided in the supply and transport of the legions, but also helped in the protection of the frontiers in the rivers Rhine and Danube. Another of its duties was the protection of the very important maritime trade routes against the threat of pirates. Therefore it patrolled the whole of the Mediterranean Sea, parts of the North Atlantic (coasts of Hispania, Gaul, and Britannia), and had also a naval presence in the Black Sea. Nevertheless the army was considered the senior and more prestigious branch