Numbers 35:1-5

And the LORD spoke to Moses in the plains of Moab by the Jordan across from Jericho, saying: “Command the children of Israel that they give the Levites cities to dwell in from the inheritance of their possession, and you shall also give the Levites common-land around the cities. They shall have the cities to dwell in; and their common-land shall be for their cattle, for their herds, and for all their animals. The common-land of the cities which you will give the Levites shall extend from the wall of the city outward a thousand cubits all around. And you shall measure outside the city on the east side two thousand cubits, on the south side two thousand cubits, on the west side two thousand cubits, and on the north side two thousand cubits. The city shall be in the middle. This shall belong to them as common-land for the cities.