Timbuktu on Unesco danger list
Timbuktu was a centre of Islamic learning from the 13th to the 17th Centuries
700,000 manuscripts survive in public libraries and private collections
Books on religion, law, literature and science
Letters between rulers, advisers and merchants on subjects as varied as taxation, commerce, marriage, divorce, adoption, and prostitution
Life in Timbuktu under Islamist rule
Why do we know Timbuktu?
The city is also home to about 700,000 ancient manuscripts held in about 60 private libraries.
Concern about Timbuktu's ancient sites was raised after a coup in March which overthrew the government.
Tuareg rebels and Islamist militants capitalised on the chaos and took control of the north of the country, but their uneasy alliance has all but collapsed.
Analysts say they do not share the same ambitions, with the Tuaregs wanting secession and Islamist fighters keen to impose Sharia law in the poor West African state.
The Tomb of Askia, a pyramidal structure which was built in 1495, is the burial place of the Emperor Mohammad Askia, who led the Empire of Songhai, one of the most successful Islamic empires in history.
Last month, al-Qaeda linked Islamist fighters were reported to have destroyed the tomb of a local Muslim saint in Timbuktu.
Strict Islamists regard shines as idolatrous, while some Muslims, especially Sufis, regard them as an accepted part of Muslim worship.