Beersheba is a place name that appears in the Bible. It usually refers to the southernmost point of the territory given to the Hebrew people. Therefore, the expression "from Dan to Beersheba" appears in the Bible, which is an idiom meaning the entire region of the Hebrew people.
Abraham stayed there for a considerable time.
Gen 21:31Therefore he called that place Beersheba, because there the two of them took an oath.
Gen 21:14Abraham got up early in the morning, took some bread and a skin of water, and gave them to Hagar, putting them on her shoulder, and sent her away with the child. And she departed and wandered in the wilderness of Beersheba.