2 Samuel 24:7

And came to the strong hold of Tyre, and to all the cities of the Hivites, and of the Canaanites: and they went out to the south of Judah, even to Beer–sheba.

Cross-reference

2 Samuel 24:2 is the earlier command to census from Dan to Beersheba, directly linking to the mention of Beersheba here as the southern endpoint.

Genesis 21:31–33 Historical context

Genesis 21:31-33 recounts Abraham naming Beersheba, the southern boundary that David's census reaches here.