The author has studied some types of Japanese castle towns constructed in the early modern ages. A specific type attracted him very much. It is a castle with wall, moat and bastions such as Gory?kaku in the south end of Hokkaido. Its plan is thought to be brought from west Europe through Dutch military books. So, in his paper ""Preliminary note on the castle towns in the Netherlands"" he tried to examine the history of castle towns in the Netherlands and to clear up the features of four typical castle towns by showing various maps and photos. In this paper, he tried to examine the history of castle towns in Belgium, using research papers, various old maps, topographical maps, air-photographs. Then, the following five facts are pointed. (1) According to 'Carte Chorographique des Pay-bas Austrichiens' (1780) fortified towns were located more closely along the border with Zeeland Province of the Netherlands and with France than in other part of Belgium. (2) In the northwestern part of Belgium covered with swampy lowlands, after fortified towns were dismantled most of their moats have remained as useful canals, such as in Bruges (Brugge), Province of West Flanders. (3) In the central part of Belgium covered with gently undulated plain, town's moats were generally filled up to construct motorway rings after dismantlement of fortifications, such as in Louvain (Leuven), Province of Brabandt. (4) In the valley of M