Rebuilt Castle Gates and Turrets: Higashi Gomon, Tatsumi Yagura, and Hitsujisaru Yagura 城門と櫓：東御門、巽櫓、坤櫓

The Higashi Gomon gate, located on the east side of the castle grounds, could only be used by important people. The gate is in the shape of an open square and has two sets of large, heavy doors. Defending forces could trap intruders who entered the gate by closing both sets of doors and attacking them from above. The thick walls of the gate have rectangular openings to accommodate bows and circular openings for guns. Hinged panels in the floorboards above the doors were used to drop rocks on attackers below.

Tatsumi Yagura (Completed 1989)

Tatsumi Yagura is a turret with a rare L-shaped design. The design of the gate dates to the large reconstruction project completed in 1638. The plans and artifacts excavated from the castle grounds are on display inside the turret. On the second floor is a reconstruction of the room at nearby Rinzaiji Temple where Tokugawa Ieyasu (1542–1616) received lessons as a boy.

Hitsujisaru Yagura (Completed 2014)

Hitsujisaru Yagura is located in the southwest corner of Sumpu Castle. Its name combines the words for sheep (hitsuji) and monkey (saru), which are associated with the cardinal directions of south (sheep) and west (monkey) in East Asian geomancy. The exhibits inside the yagura show traditional Japanese construction and building techniques. Floorboards and ceiling panels have been removed to reveal the interior structure. One exhibit explains traditional carpentry through models of traditional joinery. Another shows one method of traditional wall construction—layers of bamboo and rope covered by clay, straw, and natural plaster.