MADRID, Spain (AP) -- A shipwrecked first-century vessel carrying delicacies to the richest palates of the Roman Empire has proved a dazzling find, with nearly 2,000-year-old fish bones still nestling inside clay jars, archaeologists said Monday.

Boaters found its cargo of hundreds of amphoras in 2000 when their anchor got tangled with one of the two-handled jars.

After years of arranging financing and crews, exploration of the site off the coast of Alicante in southeast Spain began in July, said Carles de Juan, a co-director of the project, who works for the Valencia regional government.

The ship is estimated to have been 30 meters (100 feet) long with capacity for around 400 tons of cargo. That would make it twice the size of most other Roman shipwrecks found in the Mediterranean, de Juan said in an interview with the Associated Press.

The freight was an estimated 1,500 well-preserved clay amphoras, or two-handled jars, used in this case to hold fish sauce -- a prized condiment for wealthy Romans, he said.

For centuries the meter-tall amphoras lay undisturbed except for an occasional octopus that would pry one open, breaking the ceramic-and-mortar seal in search of food or shelter.

Besides the size of the ship and good condition of its cargo, the site is also important because it is so easily accessible -- in just 25 meters (80 feet) of water about 1.5 kilometers (one mile) from the coast. Other wrecks are so deep they cannot be examined by scuba divers.

"I am not going to say it was on the beach, but almost," said de Juan, who was among the first divers to examine the shipwreck in 2000.

"We knew it was an important find but had no real idea until now," de Juan said. "It is an exceptional find."