During 1968, in Ikino Matsubara near Meinohama Station, the use of sandstones and granites were confirmed in the construction of the Genk Brui, then in 1969, Basalt and granite were discovered to be used as well.
In 1958, human bones corresponding to 200 bodies were found in Imazu near the defensive structure, with ceramics considered to have been used by those convened for the construction of the wall. Ikino Matsubara near Meinohama Station Use of sandstone and granite confirmed. Basalt and granite were used, differing by location. 
