Joshua 20:3-7

so that one who commits manslaughter by killing a person unintentionally, without premeditation, may flee there, and they shall become your refuge from the avenger of blood.

Then he shall flee to one of these cities, and shall stand at the entrance of the gate of the city, and state his case in the presence of the elders of that city; and they shall receive him into the city to them and give him a place, so that he may remain among them.

Now if the avenger of blood pursues him, then they are not to hand the one who committed manslaughter over to him, since he struck his neighbor without premeditation and did not hate him previously.

And he shall remain in that city until he stands before the congregation for judgment, until the death of the one who is high priest in those days. Then he shall return to his own city and to his own house, to the city from which he fled.’ ”

So they set apart Kedesh in Galilee in the hill country of Naphtali, and Shechem in the hill country of Ephraim, and Kiriath-arba (that is, Hebron) in the hill country of Judah.