The Mali Empire reached its largest area under the Laye Keita mansas. Al-Umari, who wrote down a description of Mali based on information given to him by Abu Sa’id ‘Otman ed Dukkali (who had lived 35 years in Niani), reported the realm as being square and an eight-month journey from its coast at Tura (at the mouth of the Senegal River) to Muli (also known as Tuhfat). Umari also describes the empire as being south of Marrakesh and almost entirely inhabited except for few places. Mali's domain also extended into the desert. He describes it as being north of Mali but under its domination implying some sort of vassalage for the Antasar, Yantar'ras, Medussa and Lemtuna Berber tribes.[40] The empire's total area included nearly all the land between the Sahara Desert and coastal forests. It spanned the modern-day countries of Senegal, southern Mauritania, Mali, northern Burkina Faso, western Niger, the Gambia, Guinea-Bissau, Guinea, the Ivory Coast and northern Ghana. By 1350, the empire covered approximately 478,819 square miles (1,240,140km2).[41] The empire also reached its highest population during the Laye period ruling over 400 cities,[42] towns and villages of various religions and elasticities. During this period only the Mongol Empire was larger.