A virtual exhibition, which shows how the Elgin Marbles would look if they were reunited, has opened in London.
The Marbles were removed from Greece 200 years ago
Marbles Reunited shows those sculptures removed from Greece 200 years ago by Lord Elgin next to those which remained in Athens.
The London marbles are shown in colour while the others are depicted in white.
The exhibition was shown at the Houses of Parliament earlier in the year.
The marbles, ancient sculptures which once adorned the Parthenon in Athens, have been held in the British Museum since 1811.
The current exhibition was organised by those campaigning for them to be returned to their original home.
"There has been a misconception that the entirety of the collection is in the British Museum," said Freddie New, of the British Committee For The Restitution Of The Parthenon Marbles.
"However, this exhibition shows that this is not the case".
Other campaigners are using the forthcoming Olympics, due to be held in Greece next year, to raise the question of ownership.
"The clock is ticking towards 2004 when the whole world's eyes will be on Athens as the Olympic Games are held there," said Richard Allan MP, head of the marbles campaign group Parthenon 2004.
"We believe that it is more important than ever that the UK engages in the debate about the future display of the Parthenon Marbles."
Only part of the Poseidon sculpture is seen in the UK
However, the British Museum has said in the past that the marbles should not be reunited as it would be impossible to do so properly.
Many of the marbles are incomplete, such as Poseidon, a sculpture whose torso remains in Athens while the back and shoulders are in Britain.
In another, a foot is in London while the rest of the sculpture is still in Greece.
The exhibition is showing at London's Institute Of Contemporary Arts until Thursday. It then travels to Oxford and Cambridge.