Genesis 46:27 gives the count with quiet precision: "All the souls of the house of Jacob, which came into Egypt, were threescore and ten" — seventy people. This is the entire family of the promise. From Abraham's departure from Ur, through Isaac and Jacob, through the twelve sons and their wives and children — the entire covenant lineage that would become the nation of Israel entered Egypt as seventy people. They would exit as millions.
The journey began at Beer-sheba, the southernmost city of Canaan. God spoke to Jacob there one last time — not to stop him, but to reassure him. The patriarchs had always been warned against Egypt (Genesis 26:2, God told Isaac explicitly not to go). But now God was sending them: "Fear not to go down into Egypt; for I will there make of thee a great nation: I will go down with thee into Egypt; and I will also surely bring thee up again" (Genesis 46:3–4). This was covenant promise and divine escort simultaneously.
Look at the map. Find Goshen in the eastern Nile Delta. This fertile region — the land of Wady Tumilat and the Canal area east of the main Delta — was what Joseph had designated for his family. It was close enough to the court for Joseph to manage (find Zoan/Tanis in the Delta just north of Goshen), and productive enough for the family's flocks. Pharaoh confirmed it enthusiastically when Joseph brought five of his brothers before him: "In the best of the land make thy father and brethren to dwell" (Genesis 47:6).
The reunion at Goshen — Joseph riding out in his royal chariot to meet his father — is one of the most emotionally powerful scenes in Genesis. Jacob had been told Joseph was dead for perhaps twenty-two years. He had mourned, refused comfort, grown old in grief. And now his son came riding toward him across the Egyptian plain. "Joseph made ready his chariot, and went up to meet Israel his father, to Goshen, and presented himself unto him; and he fell on his neck, and wept on his neck a good while." Jacob said: now I can die. He had seen his son's face. He lived another seventeen years in Egypt, dying at 147.