TT #17 · Parashas Va’eschanan · Second Aliyah · Passuk 4:43
Bezer in the wilderness in the land of the plain for the Reubenites, Ramoth in Gilead for the Gadites, and Golan in Bashan for the Manassites.
Torah Temimah points to Makos 9b–10a (the three Transjordan cities aligned opposite the three cis-Jordan cities like two rows in a vineyard).
English: The Sages taught: Moshe set aside three cities on the east side of the Jordan, and corresponding to them Yehoshua set aside three in the land of Canaan; they were aligned like two rows in a vineyard — Chevron in Yehudah opposite Bezer in the wilderness, Shechem in Mount Ephraim opposite Ramoth in Gilead, Kedesh in Mount Naftali opposite Golan in Bashan.
Custom (structural parallel between the two sets of cities).
The three Transjordan cities of refuge were positioned to mirror the three cities later designated west of the Jordan, forming a balanced network across the whole Land.