Chinguetti

Chinguetti was for centuries Islam's seventh holiest city and a key crossroads on the camel caravan routes to Mecca: its old town, a UNESCO World Heritage Site, preserves family libraries holding thousands of medieval manuscripts on mathematics, astronomy and Islamic law, some over 700 years old. The desert is literally advancing over the town — real dunes creep between the stone houses — and camel-trekking tourism through the Adrar today sustains much of the local economy.