Archaeologists in Greece have located long-lost fragments from the 2,500-year-old Parthenon built into the outer walls of the Athens Acropolis, a supervising official said on Thursday.
The fragments were pinpointed after a vertical scan of the 20-metre (65-foot) walls using a camera mounted on a modified weather balloon, says Mary Ioannidou, head of the Acropolis Restoration Service.
"We have known for many years that elements from the Parthenon and other monuments have been built into the walls," Ioannidou told AFP.
"Nobody knows how many there are. But now we are almost able to touch them. This has not been done before," she said.
Some of the architectural elements are believed to be parts of the Parthenon's vaunted metopes, or square decorative frieze spaces.
They were apparently used as building materials in the wall of the Acropolis -- a fortress for centuries -- during the 18th century.
The use of architectural elements from temples and other buildings in fortifications was commonplace in Greek antiquity and later periods.
The Parthenon has sustained significant damage in its long history. It was bombarded during a 17th century Venetian siege of Ottoman-held Athens and underwent modifications that turned it first into a church and then a mosque.
In the early 19th century, workers employed by British ambassador Lord Elgin tore down a large number of decorative friezes from the Parthenon.
They were shipped to London and were eventually put on display at the British Museum where they remain to this day.
The Museum has turned down Greek calls for their return, arguing that the Marbles are part of a world heritage and are more accessible to visitors in London.
"It was originally believed that Elgin had taken all the fragments," Ioannidou said on Thursday. "As it turns out, he did not."
