The succession of wars forced the emperors to found new castles in strategically sensitive regions. The most important is the Gynaikokastro (in the prefecture of Kilkis), built by Andronikos III Palaeologos.
In central and eastern Macedonia several isolated towers dating from the 13th to the 14th century are encountered. These belonged to monasteries on Mount Athos and were used for storing the produce cultivated on their estates, while at the same time controlling the overland routes.
"Industrial" buildings include an oil-press (1324/25) in an extensive old olive grove on the north shore of Lake Volvi, and seven water mills on streams east and west of Thessalonike. In the city itself, a rare for its period (13th to 14th century) bath-house is preserved, which remained in use until 1940.