It has been 200 years since the Greek Parthenon marbles were taken from Athens by a Scottish lord and sold to the British government.
The sculptures now sit in the British Museum, where they have become a source of national injustice for many Greeks, who say they were removed illegally and should be returned.
There are thousands of artefacts around the world that have been stolen, sold or traded through dubious means - and some countries want them back.
Some of the most controversial pieces are Egyptian.
They include the Rosetta Stone, discovered by a Frenchman and later acquired by the British, as well as the bust of Queen Nefertiti, discovered by a German archaeologist, which now sits in a Berlin museum.
The Egyptian government wants both pieces returned.
Other disputed artefacts include the Indian Koh-i-Noor diamond, one of the largest in the world. It was taken by Britain's East India Company and presented to Queen Victoria.
Should nations have the right to reclaim cultural property that may have been wrongly taken in the past?
Presenter: Hazem Sika
Peter Stewart - Associate Professor of Classical Art and Archaeology at Oxford University.
Nadia Banteka - Lecturer in International Law at the Hague University.
Amr Al Azm - Associate Professor of Middle East History and Anthropology at Shawnee State University.
Source: Al Jazeera