Numbers 35:3-5

3The cities will be for them to live in, and their pasturelands will be for their herds, flocks, and all their other animals.

4The pasturelands of the cities you are to give the Levites will extend from the city wall five hundred yards on every side.

5Measure a thousand yards outside the city for the east side, a thousand yards for the south side, a thousand yards for the west side, and a thousand yards for the north side, with the city in the center. This will belong to them as pasturelands for the cities.