The vessels that Greek merchants used in ancient times were meticulously crafted by expert shipbuilders, although the science of the day presented serious flaws that pirates could easily use to their advantage. Grecian ports and harbors were often relatively shallow, and it was common practice to build vessels with wide beams and flat bottoms that could literally be hauled onto the shore by the crew. Because of the shallow draft design, heavily laden merchant vessels were clumsy and slow, presenting perfect prey for smaller and much nimbler pirate craft.
The nearly intact recovered remains of a Greek trading vessel that has been carbon dated to 350 B.C. is illustrative of merchant ships of the era. About 50 feet in length and 15 feet across, the ship was capable of carrying an estimated seven tons of cargo. Fully loaded, the deck of the ship would ride only 2 feet above the surface of the water, and the single square-rigged sail could provide a speed of about five knots.
Unescorted by protective warships, such vessels would have no defense and no escape from the swift oar-propelled craft favored by pirates of the day. Piracy would continue to tax the patience and commercial aspirations of ruling nations in the Mediterranean Sea well into the era of Roman rule, and into northern Europe, where the Vikings would begin wreaking their own brand of terror and plunder.