God knows that people of Israelites need a City of Refuge - And the Lord spoke to Moses, saying, “Speak to the people of Israel and say to them, When you cross the Jordan into the land of Canaan, then you shall select cities to be cities of refuge for you, that the manslayer who kills any person without intent may flee there.  The cities shall be for you a refuge from the avenger, that the manslayer may not die until he stands before the congregation for judgment. And the cities that you give shall be your six cities of refuge. You shall give three cities beyond the Jordan, and three cities in the land of Canaan, to be cities of refuge. These six cities shall be for refuge for the people of Israel, and for the stranger and for the sojourner among them, that anyone who kills any person without intent may flee there.

“But if he struck him down with an iron object, so that he died, he is a murderer. The murderer shall be put to death. And if he struck him down with a stone tool that could cause death, and he died, he is a murderer. The murderer shall be put to death. Or if he struck him down with a wooden tool that could cause death, and he died, he is a murderer. The murderer shall be put to death. The avenger of blood shall himself put the murderer to death; when he meets him, he shall put him to death. And if he pushed him out of hatred or hurled something at him, lying in wait, so that he died, or in enmity struck him down with his hand, so that he died, then he who struck the blow shall be put to death. He is a murderer. The avenger of blood shall put the murderer to death when he meets him.

“But if he pushed him suddenly without enmity, or hurled anything on him without lying in wait or used a stone that could cause death, and without seeing him dropped it on him, so that he died, though he was not his enemy and did not seek his harm, then the congregation shall judge between the manslayer and the avenger of blood, in accordance with these rules - Numbers 35:9-24

And this City of Refuge is so critical for everyone, so again God spoke to Joshua about this - Then the Lord said to Joshua, “Say to the people of Israel, ‘Appoint the cities of refuge, of which I spoke to you through Moses, that the manslayer who strikes any person without intent or unknowingly may flee there. They shall be for you a refuge from the avenger of blood. He shall flee to one of these cities and shall stand at the entrance of the gate of the city and explain his case to the elders of that city. Then they shall take him into the city and give him a place, and he shall remain with them. And if the avenger of blood pursues him, they shall not give up the manslayer into his hand, because he struck his neighbor unknowingly, and did not hate him in the past - Joshua 20:1-5

So Moses and Joshua identified six places as City of Refuge - 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. And beyond the Jordan east of Jericho, they appointed Bezer in the wilderness on the tableland, from the tribe of Reuben, and Ramoth in Gilead, from the tribe of Gad, and Golan in Bashan, from the tribe of Manasseh. These were the cities designated for all the people of Israel and for the stranger sojourning among them, that anyone who killed a person without intent could flee there, so that he might not die by the hand of the avenger of blood, till he stood before the congregation - Joshua 20:7-9