If the opinion that relies on the Red Sea route focuses on the Hijaz, its cities, and its ports opposite the Sudanese coast, then it is undeniable that it was a route for Arab migration, but it was not the main route taken by the vast Arab migration to Sudan. However, all those migrations occurred from the Arabian Peninsula, and they may have taken several routes of migration to Sudan. I have pointed to the route of the main Islamic migrations to Sudan, but we emphasize that the Red Sea route did not witness large-scale Arab migrations like the other routes that participated in the migration movement to Sudan. The Nile Valley has been used as a primary passage for migration to Sudan since the invasion by Abdullah bin Saad bin Abi Al-Sarh to the land of Nubia, reaching Dongola in 31 AH / 651 AD. He wrote a covenant for the people of Nubia, stipulating that they protect the old mosque built by the Muslims in Dongola, which might have been built sufficiently before this invasion. He also stipulated that they protect Muslim merchants and other Muslims who were moving in collective or individual migration and who were leaving their countries. Thus, Abdullah bin Saad bin Abi Al-Sarh laid a strong foundation that paved an easy and smooth path for what happened in the penetration of Muslim Arabs in a large migration movement to this country. Similarly, since the Umayyad era, Arabs residing in Aswan and the south began buying some lands and estates from the Nubians, and then they began investing these lands until they owned many estates within the lands of Nubia in the region called the land of Al-Mairis, which ends approximately at the Second Cataract. Similarly, when the Abbasids marched on Egypt to end the Umayyad rule there, the advancing Abbasid army met the Umayyad army.