God promises to appoint cities of refuge for those who accidentally killed their brethren.
Exodus 21:12-13 NASB
[12]"He who strikes a man so that he dies shall surely be put to death. [13]But if he did not lie in wait for him, but God let him fall into his hand, then I will appoint you a place to which he may flee
We know that after their had conquered the transjordan cities they set aside three cities for that purpose and another three after crossing the Jordan
Joshua 21:21,27,32,36,38
[21]They gave them Shechem, the city of refuge for the manslayer, with its pasture lands, in the hill country of Ephraim, and Gezer with its pasture lands, [27]To the sons of Gershon, one of the families of the Levites, from the half-tribe of Manasseh, they gave Golan in Bashan, the city of refuge for the manslayer, with its pasture lands, and Be-eshterah with its pasture lands; two cities. [32]From the tribe of Naphtali, they gave Kedesh in Galilee, the city of refuge for the manslayer, with its pasture lands and Hammoth-dor with its pasture lands and Kartan with its pasture lands; three cities. [36]From the tribe of Reuben, they gave Bezer with its pasture lands and Jahaz with its pasture lands, [38]From the tribe of Gad, they gave Ramoth in Gilead, the city of refuge for the manslayer, with its pasture lands and Mahanaim with its pasture lands,
All this took place some forty years after their wanderings in the wilderness.
But what happened to the manslayer during those forty years of wandering in the wilderness?