Numbers 35:8

5 And ye shall measure without the city for the east side two thousand cubits, and for the south side two thousand cubits, and for the west side two thousand cubits, and for the north side two thousand cubits, the city being in the midst. This shall be to them the suburbs of the cities.

6 And the cities which ye shall give unto the Levites, they shall be the six cities of refuge, which ye shall give for the manslayer to flee unto: and besides them ye shall give forty and two cities.

7 All the cities which ye shall give to the Levites shall be forty and eight cities; them [shall ye give] with their suburbs.

8 And concerning the cities which ye shall give of the possession of the children of Israel, from the many ye shall take many; and from the few ye shall take few: every one according to his inheritance which he inheriteth shall give of his cities unto the Levites.

9 And Jehovah spake unto Moses, saying,

10 Speak unto the children of Israel, and say unto them, When ye pass over the Jordan into the land of Canaan,

11 then ye shall appoint you cities to be cities of refuge for you, that the manslayer that killeth any person unwittingly may flee thither.