A small navy had operated at a fairly low level after the Second Samnite War, but it was massively upgraded during this period, expanding from a few primarily river- and coastal-based patrol craft to a full maritime unit. After a period of frenetic construction, the navy mushroomed to a size of more than 400 ships on the Carthaginian pattern. Once completed, it could accommodate up to 100,000 sailors and embarked troops for battle. The navy thereafter declined in size. This was partially because a pacified Roman Mediterranean called for little naval policing, and partially because the Romans chose to rely during this period on ships provided by Greek cities, whose peoples had greater maritime experience.