Since only castles built of stone and walled towns had been able to resist Mongol attacks, following the withdrawal of the Mongols the kings encouraged both the landowners and the townspeople to build stone fortifications. New stone fortresses were built, for example, at Codlea, Rimetea, and Unguraş. The process of urbanization was characterized by the predominance of the Saxon towns: out of the eight towns in Transylvania, only Alba Iulia and Dej were situated in the counties. A charter referring to inns, bakeries, and bathhouses in Rodna proves the city-like way of life of its inhabitants. Salt was still the most important item of trade in this period, but trading with oxen, maidservants, and wine is also documented in royal charters.