From the Register:

Athenian triremes were legendary warships, the guided missiles of their day.

The human-powered vessels defeated a much larger Persian fleet at the Battle of Salamis, and in the process rescued Western civilization from likely oblivion.

The trireme was celebrated and much written about by Thucydides and other Greeks of the 5th century B.C. But nobody recorded any plans or specifications.

Consequently, later historians could only make educated guesses about the size, construction and configuration of the craft. The only clues came from a fragment of the relief in the Acropolis, images on shards of pottery, a joke in a play by Aristophanes, and a few other sparse references.

"Historians were arguing in the 1970s and 1980s about what did a trireme look like," said William Abbott, associate professor of history at Fairfield University. "It was a ramming ship, and probably made of light wood. It was rowed by a crew of 170, probably in three levels."

What else could the "tri" in trireme mean? Three men to an oar? Or three rows of one-man oars?

The Lenorman relief, removed from the Acropolis in 1852, seems to show three tiers of rowers.

In the mid-1980s, naval architect John F. Coates and others who would eventually found the Trireme Trust decided to build a trireme. The project was financed by the Greek navy and cost about $1 million.

The resulting craft, the Olympia, is now the world's only trireme.

The Olympia is resting in Greece, and the Trireme Trust hopes to bring it to New York Harbor in 2010. Meanwhile, any photograph of a trireme that you see is the Olympia.

Ford Weiskittel, director of the Trireme Trust and a former collegiate rower, saw the project through — selecting a crew and eventually eking about 9 knots out of Olympia.

Unlike other historical ships preserved in silt, triremes were buoyant, Weiskittel said. They floated, rather than sank, either to be towed away and repaired or washed ashore to rot.

Archeologists found the remnants of shelters built along the shore to house triremes. The foundations suggested that the ships were about 120 feet long and 18 feet wide, making them extremely narrow.

This length is optimal for balancing the opposing bow and stern waves that would otherwise stress and weaken the ship, Weiskittel said.

Contrary to public belief, trireme crews were not slaves. "Rowers were highly skilled and well paid," he said. Crews trained eight months a year at propelling and maneuvering a trireme.

Coordinating 170 oars required tremendous skill, not to mention turning the craft and attacking the enemy, Weiskittel said. Coates, and others, considered how the three decks of rowers would have fit into the ship.

All oars had to be the same length, and all met the water at the same distance from the side of the ship.

That left a limited number of ways for the crew to be seated. Coates and others decided that the most likely design, which also resembled the ship in the relief, had rowers on deck, another line lower and a foot or two down, and a third line in what would have been the ship's hold.

All the rowers could fit in this configuration, and could row without bumping into crew mates. The Olympia showed that rowing was exhausting and difficult in the confined spaces, and the lowest rowers could not see out of the ship.

Triremes were built of light wood, and likely assembled with mortise and tenon joints to save weight, Weiskittel said. Light ribs supported the inside of the hull.

A key part of the ship, the hypozoma, was a powerful, taut rope connected from the bow to the stern. It stiffened the hull and kept the craft true. The keel extended through the bow and ended in a 400-pound, bronze ram.

A ram was found and reproduced. Tellingly, the ram does not end in a point. Rather, it widens, and has side ridges intended to restrict the depth of penetration.

The goal of ramming would have been to pierce the hull of the enemy ship, not to bury the prow in the target, which would have allowed enemy soldiers to board and slaughter the crew.

Weiskittel said the apparent tactics of triremes would have been to maneuver behind the enemy and then ram the stern. The trireme would then withdraw and allow the other ship to fill with water and sink.

The Olympia never had the opportunity to ram anything. The crew achieved 7 knots, which is about the speed a trireme would have traveled, given various historical accounts.

With practice, the crew could turn the ship in a circle only slightly longer than the length of the vessel. They could accelerate from zero to 7 knots in about 30 seconds.

Weiskittel picked male and female crew members between 5-foot-4 and 5-foot-7 to duplicate the likely stature of ancient Greek men. Even so, the lowest line of rowers had to bend their heads to avoid hitting a beam in front of them, and inevitably bumped the backs of their heads on the return stroke.

Since no one is sure of the water level of the Aegean Sea in ancient times, or how far ashore the triremes were dragged, it's possible the ships were 3 to 4 feet longer than the Olympia, Weiskittel said. This would give the crew more rowing room.

The trireme bested Xerxes' fleet at the Battle of Salamis, sinking or capturing more than 200 enemy vessels in the narrow straits between Piraeus and Salamis, a small island in the Saronic Gulf, near Athens.

If Xerxes had won, the triremes smashed to splinters, then what?

No more Athens, no more democracy, and probably no Plato or Aristotle.

"The Battle of Salamis was a huge impetus for Greeks and democracy," Weiskittel said.

Or, as some historians and trireme enthusiasts see it, Western civilization.

... and as long as we're talking about triremes, we might as well mention this bit of ClassCon from the incipit and conclusion to a piece in the Motley Fool:

Had the crew of an ancient Greek trireme crossed paths with a member of Aegean Marine's (NYSE: ANW) fleet, there's no telling how they might have reacted.

As far-ranging as their hollow ships may have been, the mariners of Homer's day would have soiled their tunics had they known the extent of wine-dark sea now covered by this fuel transporter. Aegean provides fuel to oil tankers, container ships, drybulk carriers, cruise ships, ferries, and other shipping vessels both at sea and in port, and it operates all over the world. Last Thursday, it reported quarterly diluted earnings per share of $0.22 on $951 million in total revenues -- higher than last year's fiscal third quarter by 22% and 167%, respectively.

[...]

If you're brave like Achilles and unafraid of its risks, you might consider how an investment in Aegean's stock would fit into your already well-diversified portfolio.