Destroying the past: Cultural heritage in extremist crosshairs
How to protect such sites is set to be a hot topic at a December conference in Abu Dhabi, with envoys from around 40 countries expected to attend.
Here are some major world cultural sites destroyed or damaged by recent conflicts.
More than 900 monuments or archaeological sites have been looted, damaged or destroyed by the regime, rebels or extremists in Syria, where war has raged since 2011, according to the association charged with protecting Syrian architecture.
In UNESCO-listed Palmyra, which the Islamic State group occupied from May 2015 to March 2016, fighters destroyed two of the most important temples and several famous tower tombs as they pursued their campaign to erase some of the most important cultural heritage sites in the Middle East.
Other notable sites damaged or looted include Dura-Europos in eastern Syria, once known as the "Pompeii of the desert", Apamea and Tal Ajaja.
However, IS is not alone in ravaging Syrian heritage, with all sides looting and destroying ancient sites.
In the northern city of Aleppo, fighting in 2013 destroyed the 11th century minaret of the city's famed Ummayad mosque.
There has also been extensive damage to the city's ancient covered market, and its citadel was damaged by an explosion in July 2015.
"Two thirds of the ancient city of Aleppo have been bombarded and set on fire," according to UNESCO.
The Crac des Chevaliers crusader castle near the central city of Homs has also been hit by fighting, and the famous mosaic museum at Maaret al-Numan has been seriously damaged.
Government soldiers have also been accused of looting sites.
IS has carried out a campaign of "cultural cleansing", razing many ancient Mesopotamian relics and looting others to sell on the black market.
Nimrud, a jewel of the Assyrian empire south of Mosul, founded in the thirteenth century, has recently been retaken from IS by Iraqi forces after being devastated.
Videos released in 2015 showed IS using bulldozers and explosives to destroy Nimrud, and ransacking pre-Islamic treasures in Mosul's museum.
They also attacked Hatra, a Roman-period site, in the northern Nineveh province.
Fabled desert city Timbuktu, dubbed the "City of 333 saints" and designated by UNESCO in 2012 as a world heritage site in danger, was attacked for months by extremists bent on imposing a brutal version of Islamic law.
In June 2012, al-Qaeda-linked militants destroyed 14 of the northern city's mausoleums, major structures dating back to Timbuktu's golden age in the 15th and 16th centuries when it was an economic, intellectual and spiritual hub.
Reconstruction began in March 2014, relying heavily on traditional methods and employing local masons. Several countries and organisations financed the reconstruction, including UNESCO.
On September 27, a Malian was sentenced to nine years in jail by the International Criminal Court for his part in the destruction.
Several mausoleums have been destroyed by Islamist extremists since Muammer Gaddafi was overthrown in 2011.
In August 2012, hardliners blew up the mausoleum of Sheikh Abdessalem al-Asmar in the western city of Zliten, as well as another in Misrata.
In 2013, suspected Islamic extremists attacked the 16th century mausoleum of Murad Agha near Tripoli, but did not reach the tomb inside.
In March 2001, Taliban leader Mullah Omar, who died in 2013, ordered the destruction of two 1,500-year-old Buddha statues in the eastern town of Bamiyan because they were deemed anti-Islamic.
Hundreds of Taliban militants spent weeks demolishing the gigantic statues carved into the side of a cliff.
In 2003, the Bamiyan Valley was declared a World Heritage Site by UNESCO.
In Algeria in the 1990s, Islamist groups destroyed numerous sanctuaries.