Quinquereme
An ancient Roman or Carthaginian galley with five banks of oars on each side.
Perhaps the most famous of the Hellenistic-era warships, because of its extensive use by the Carthaginians and Romans, the quinquereme was invented by Dionysius I of Syracuse in 399 BC as part of a major naval armament programme directed against the Carthaginians. During most of the 4th century, the “fives” were the heaviest type of warship, and often used as flagships of fleets.

OK, we know the oarsmen were largely slaves but all those oars! The image is a model of a trireme (three banks of oars); just imagine adding another two banks of oars to that! They must have been a nightmare to power and even more of a nightmare to handle. But if done right they would have been awe-inspiringly impressive.