ALEXANDRIA, Egypt — Plunging into the waters off Alexandria Tuesday, divers explored the submerged ruins of a palace and temple complex from which Cleopatra ruled, swimming over heaps of limestone blocks hammered into the sea by earthquakes and tsunamis more than 1,600 years ago.
The international team is painstakingly excavating one of the richest underwater archaeological sites in the world and retrieving stunning artifacts from the last dynasty to rule over ancient Egypt before the Roman Empire annexed it in 30 B.C.
Using advanced technology, the team is surveying ancient Alexandria's Royal Quarters, encased deep below the harbor sediment, and confirming the accuracy of descriptions of the city left by Greek geographers and historians more than 2,000 years ago.
Since the early 1990s, the topographical surveys have allowed the team, led by French underwater archaeologist Franck Goddio, to conquer the harbor's extremely poor visibility and excavate below the seabed. They are discovering everything from coins and everyday objects to colossal granite statues of Egypt's rulers and sunken temples dedicated to their gods.
"It's a unique site in the world," said Goddio, who has spent two decades searching for shipwrecks and lost cities below the seas.
The finds from along the Egyptian coast will go on display at Philadelphia's Franklin Institute from June 5 to Jan. 2 in an exhibition titled "Cleopatra: The Search for the Last Queen of Egypt." The exhibition will tour several other North American cities.
Many archaeological sites have been destroyed by man, with statues cut or smashed to pieces. Alexandria's Royal Quarters — ports, a cape and islands full of temples, palaces and military outposts — simply slid into the sea after cataclysmic earthquakes in the fourth and eighth centuries. Goddio's team found it in 1996. Many of its treasures are completely intact, wrapped in sediment protecting them from the saltwater.
"It's as it was when it sank," said Ashraf Abdel-Raouf of Egypt's Supreme Council of Antiquities, who is part of the team.
Tuesday's dive explored the sprawling palace and temple complex where Cleopatra, the last of Egypt's Greek-speaking Ptolemaic rulers, seduced the Roman general Mark Antony before they committed suicide upon their defeat by Octavian, the future Roman Emperor Augustus.
Dives have taken Goddio and his team to some of the key scenes in the dramatic lives of the couple, including the Timonium, commissioned by Antony after his defeat as a place where he could retreat from the world, though he killed himself before it was completed.
They also found a colossal stone head believed to be of Caesarion, son of Cleopatra and previous lover Julius Caesar, and two sphinxes, one of them probably representing Cleopatra's father, Ptolemy XII.
Divers photographed a section of the seabed cleared of sediment with a powerful suction device. Their flashlights glowing in the green murk, the divers photographed ruins from a temple to Isis near Cleopatra's palace on the submerged island of Antirhodos.
Among the massive limestone blocks toppled in the fourth century was a huge quartzite block with an engraving of a pharaoh. An inscription indicates it depicts Seti I, father of Ramses II.
"We've found many pharaonic objects that were brought from Heliopolis, in what is now Cairo," said Abdel-Raouf. "So, the Ptolemaic rulers re-used pharonic objects to construct their buildings."
On the boat's deck, researchers displayed some small recent finds: imported ceramics and local copies, a statuette of a pharaoh, bronze ritual vessels, amulets barely bigger than a fingernail, and small lead vessels tossed by the poor into the water or buried in the ground as devotions to gods.
Alexandria's Eastern Harbor was abandoned after another earthquake, in the eighth century, and was left untouched as an open bay — apart from two 20th century breakwaters — while modern port construction went ahead in the Western Harbor. That has left the ancient Portus Magnus undisturbed below.
"We have this as an open field for archaeology," Goddio said.