The "san-no-maru", which is also called the "san-no-kuruwa", covers a large proportion of this inner castle and is divided into an eastern section and a western section by the Matsunoki-zaka Approach, Takayashiki, and the stone walls between them. The foundation level of the western section is 5–6 metres (16–20 ft.) above sea level, while the eastern section is 2–3 metres higher than the western section within the mound lines along the moats, which were 8–17 metres above sea level. The height of Takayashiki is approximately 13 metres (43 ft).