Djenné-Djenno (also Jenne-Jeno) is a UNESCO World Heritage Site located in the Niger River Valley in the country of Mali. Literally translated to "ancient Djenné", it is the original site of Djenné, Mali and considered to be among the oldest urbanized centers and the best known archaeology site in sub-Saharan Africa. This archaeological site is located about 3 Kilometers away from the modern town, and is believed to have been involved in long distance trade and possibly the domestication of African rice. The site is believed to exceed 82 acres; however this has been yet to be confirmed with extensive survey work. With the help of archaeological excavations mainly by Susan and Roderick McIntosh, the site is known to be occupied from 250 B.C. to 900 A.D. The city is believed to have been abandoned and moved where the current city is located due to the spread of Islam and the building of the Great Mosque of Djenné. Previously, it was assumed that advanced trade networks and complex societies did not exist in the region until the arrival of traders from Southwest Asia.