Joshua 21:40

Overview - Joshua 21
1	Eight and forty cities given by lot, out of the other tribes, unto the Levites.
43	God gives the land, and rest unto the Israelites, according to his promise.

Joshua 21:40  (King James Version)
So all the cities for the children of Merari by their families, which were remaining of the families of the Levites, were by their lot twelve cities.