CAPE GELIDONYA, TURKEY

Archaeologists long assumed the Greeks ran the economic show in the Mediterranean during the Late Bronze Age. Then, in the summer of 1960, George Bass excavated a ship dating to 1200 B.C. off the southern coast of Turkey. The vessel-the first completely excavated underwater-was carrying Near Eastern plaques (below), copper ingots, and other goods from the East to Greece, not vice versa. The site upended conventional wisdom about Bronze Age trade and marked the beginning of scientific underwater archaeology.

STOCKHOLM HARBOR

In 1628 the ornate Swedish warship Vasa (below) sank less than a mile into its maiden voyage. In 1961 archaeologists raised the ship from the seabed, making it the first major shipwreck to be recovered almost intact, and giving researchers a unique look at 17th-century naval warfare. In the early 2000s large deposits of sulfuric salts were found eating away at Vasa’s hull, prompting researchers to develop new conservation methods that could help save Vasa and other excavated ships.

ROSKILDE, DENMARK

Most shipwrecks are the victims of unforeseen catastrophe, but five Viking-era ships excavated in 1962 near the Danish town of Roskilde, outside Copenhagen, were sunk on purpose. The ships (detail, above) formed part of an underwater rock barrier that was constructed in the 11th century to protect Roskilde from sea raids. Centuries underwater had made matchsticks of the ships’ hulls, but researchers managed to piece them together from more than 100,000 splintered bits of wood. The vessels gave archaeologists an unprecedented look at Viking shipbuilding techniques.

TAKASHIMA ISLAND, JAPAN

Legend has it that when Kublai Khan, the Mongol emperor of China, invaded Japan in 1281, his fleet was destroyed by a typhoon the Japanese dubbed a kamikaze, or “divine wind.” Celebrated in art (such as the 19th-century engraving below), the tale persisted, unproven, until the 1980s, when archaeologists diving off the small island of Takashima found copper coins, metal helmets, and arrowheads dating to the 13th century. Last year’s discovery of the substantial remains of a ship confirmed that the khan’s fleet has indeed been found.

OUTER BANKS, NORTH CAROLINA

On December 31, 1862, the USS Monitor sank in rough waters off the coast of North Carolina, carrying 16 Union sailors to their deaths. The wreckage of the ironclad warship was discovered by sonar in 1973. Over the next 20 years, archaeologists removed 210 tons of relics from the seafloor, including the ship’s iconic gun turret (seen in an 1862 photograph above) and more intimate objects like buttons and silverware used by the sailors on board. While conserving the ship’s remains, researchers were able to study the inside of Monitor’s 20-ton, 400-horsepower engine, one of the most advanced of its time.

PORT ROYAL, JAMAICA

Shipwrecks are not the only important archaeological sites preserved underwater. Nestled along the southern Jamaican coast are the remains of Port Royal, a colonial city (and pirate haven) that partially sank into the sea after a devastating earthquake in 1692; some of the town’s neighborhoods dropped 15 feet in an instant. Excavated from 1981 to 1990, Port Royal offers a glimpse into both the panicked moments after the earthquake and the everyday lives of Port Royal’s 17th-century residents, commoners who rarely show up in historical documents. Archaeologists have made discoveries both poignant-a pocket watch from the site forever set to 11:40 a.m., around the time of day the earthquake hit-and prosaic, such as hair clippings, perhaps from a pirate’s recent haircut, and intact glass liquor bottles (right).

BIG SUR, CALIFORNIA

Imagine the Titanic floating overhead: That’s what it would have been like to see the USS Macon fly by. Nearly 800 feet long, the airship was completed in 1933 as part of an effort to equip the U.S. Navy with airborne military bases. With an onboard hangar, Macon (below) was capable of launching five small fixed-wing planes in midair, but it never saw action and went down off California’s Big Sur coast during a storm in 1935. Rediscovered in 1980 when a fisherman caught a piece of the airship’s debris in his net, the wreck was recently surveyed and mapped using sonar and remotely operated robots. Government archaeologists continue to explore the unique site, which lies in 1,500 feet of water.

NORTH CAROLINA COAST

In the early 18th century, Blackbeard was the most feared of the pirates who preyed on vessels traveling to and from the American colonies. His specter returned in 1996, when archaeologists searching off the North Carolina coast discovered Blackbeard’s flagship, the Queen Anne’s Revenge, which ran aground in 1718 as the pirates fled English warships. A team has excavated at the site ever since, recovering cannons, a copper disk depicting Queen Anne herself (below), and personal effects such as pipes. What the crew left behind and what they took as they evacuated tell researchers what pirates of that period valued most-information that ships’ logs did not record.

BAJO DE LA CAMPANA, SPAIN

Along Spain’s southeastern coast, a treacherous rock formation called Bajo de la Campana has claimed many ships through the years. They included a 7th-century B.C. Phoenician trading vessel of a type depicted in contemporary wall reliefs (below). The recent excavation of the ship opened a window onto the maritime economy of the Phoenicians, a Near Eastern people who built a trading empire throughout the Mediterranean from 1500 to 600 B.C. As it sank, the ship left a trail of artifacts on the seafloor, including tin ingots, elephant tusks, and vials of perfumed oils, illustrating just how active the Phoenician trading system was. The vessel was most likely bound for a Phoenician colony just north of the wreck site.

BANKS ISLAND, CANADA

The British navy sent Investigator to the Arctic in 1850 to search for a doomed expedition led by explorer John Franklin. But Investigator was also unlucky. Its crew abandoned the ship after it was trapped in ice 500 miles north of the Arctic Circle. In 2010 archaeologists used sonar to find the ship sitting upright in 36 feet of water. Dives at the wreck gave researchers a new look at how the British outfitted vessels for polar navigation. Modifications made to strengthen the bow (below) and hull against ice allowed the wreck to survive virtually unscathed for 160 years.

By Mary Beth Griggs