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The Shiganshina District (シガンシナ区 Shiganshina-ku?) is a town located on the south edge of Wall Maria; and is the hometown of Eren Yeager, Armin Arlert, and Mikasa Ackerman. The district is built within an outcrop of Wall Maria. Since Shiganshina is located to the south, Titans usually came to this district's Walls in an attempt to consume humans, but were only able to break through in the year 845 because of the 60 meters high Colossus Titan.
In the year 845, the Colossus Titan breached Wall Maria and the front gate of Shiganshina by kicking a hole through it, allowing Titans to overrun the city. Shortly afterwards, the Armored Titan broke down the back gate, fully breaching Wall Maria and forcing humanity to abandon Wall Maria and retreat behind Wall Rose. It is also the first city to be attacked by the Titans after a century of peace.
There is little mention of Shiganshina after the attack. Erwin decides to appear at the recruitment ceremony of the 104th Training Corps to persuade them to join the Survey Corps. Erwin mentions the basement in Eren's house, and how it can hold the answer to the mystery of the Titans. He also explains that by accessing his basement, they would need to find a way to reclaim Shiganshina and Wall Maria altogether. A month later, Erwin and the Survey Corps set out on the 57th expedition as a practise run to Shiganshina.
After Reiner Braun, Bertolt Hoover and Ymir manage to escape from the Survey Corps in the Titan Forest, they head towards Shiganshina. They rest above the Wall and have a conversation, in which Ymir confesses that she wants to go with them in order to repay them for the death of Marcel Galliard.
When the plans to retake Wall Maria are ready, the Survey Corps start an expedition towards Shiganshina at night time, when most of the Titans would be shutting down. As the soldiers arrive in the district, they begin the operation and 100 soldiers travel to the exterior gate covered with hoods and cloaks in an attempt to confuse the enemy so they would not know what soldier is Eren. After making his way to the top of the Wall, Eren freezes when he sees his hometown for the first time in 6 years, but is quickly pushed on by Levi and he makes his way to the gate, preparing to transform. Finally, Eren transforms and seals the hole with his hardened Titan body.
However, their seeming success is soon interrupted by the arrival of the Armored Titan and the Colossus Titan, during which the latter kills most of the soldiers inside the district and destroys much of the abandoned city, save for the members of Squad Levi and some stragglers. During this, the Beast Titan wipes out the soldiers evacuating the Corps' horses, fatally wounding Erwin Smith in the process. However, a last-ditch assault concocted by the survivors sees the Armored and Colossus Titans successfully incapacitated, with Reiner Braun and Bertolt Hoover captured alive. The Beast Titan is also disarmed by Levi, who wipes out his army of Titans surrounding the district. The battle sees the near-death of Armin Arlert, who is administered the Titan injection by Levi and resurrects as a Titan shifter. While Zeke and Reiner are rescued by the Cart Titan, Bertolt is eaten alive by the transformed Armin as the remaining Warriors are forced to retreat from Shiganshina.
Nine months later, after all the Titans inside Wall Maria had been killed with the Titan guillotines, the former residents of Shiganshina returned to live in the city.