Numbers 32:24

32:24 So build cities for your descendants and pens for your sheep, but do what you have said you would do.”

Numbers 35:2

35:2 “Instruct the Israelites to give the Levites towns to live in from the inheritance the Israelites will possess. You must also give the Levites grazing land around the towns.

Numbers 35:11

35:11 you must then designate some towns as towns of refuge for you, to which a person who has killed someone unintentionally may flee.