Himiko's Palace is easily the biggest building in Sei'an City, able to be viewed from anywhere. Its distinguishable flame-like rooftop sets it apart from other buildings within the city. The palace complex consists of the main building, two side buildings, the palace grounds, and a small lake towards the rear of the complex. The main building of the palace contains a main lobby, as well as an elevator that leads to the throne room. A pool of lava must be crossed in order to reach the throne room itself, however.
Other small buildings lie to the east and west of the main building. They are mostly used for storage, however the east building contains a passage that connects to Ankoku Temple. The palace grounds contain boulders and decorative trees, as well as two walkways that lead to a clover and a Stray Bead. The lake consists of a torii gate as well as Himiko's grave, which can be sprinkled with Waterspout in order to obtain the Deluge secret Celestial Brush technique.
Himiko's Palace was where the ruler of Nippon, Himiko, resided during the events of Ōkami. Upon Amaterasu and Issun's arrival in Sei'an City, the queen had shut herself within her palace in order to pray for the well being of her townspeople, who were suffering from a fatal illness and the rampaging Water Dragon. Himiko ordered her soldiers to restrict all access to her quarters; as a result, Amaterasu was denied entry into the palace grounds.
Later, when Blight was defeated and the acrid fog which plagued the city vanished, Amaterasu was able to use her newly acquired Veil of Mist Celestial Brush technique in order to sneak past the guards and into the palace grounds. Within the palace, Himiko's handmaiden announced that the queen was expecting Amaterasu and Issun to arrive, and was waiting for them on the top floor. Amaterasu immediately entered the elevator which led to the throne room, but was stopped due to a large pool of lava that impeded her progress. She would later return with the Fire Tablet in hand, so she could simply swim across the lava and enter the throne room unharmed.
In the throne room, Amaterasu and Issun came face-to-face with Himiko herself. Against all expectations, the queen was not her cowardly self as Issun had expected. Himiko explained why she had locked herself away, including the Oni Island ordeal and her own Crystal ball. She then sent Amaterasu to North Ryoshima Coast to find a way to calm the Water Dragon and open a way to Oni Island.
Later on, Amaterasu and Issun chased the ghost of the priestess Rao into a tunnel that led to the palace grounds. Confused as to what was going on, the two decided to inquire Himiko about the current situation. However, when they reached the throne room, Himiko was found brutally murdered on the floor, with her crystal ball nearby. Rao appeared and revealed herself to actually be the Dark Lord, Ninetails, in disguise. Evil Rao proceeded to duel Amaterasu in the palace's throne room, with Amaterasu declared victorious. However, Ninetails scrapped Rao's body and assumed its true form, injuring Amaterasu and fleeing to Oni Island. Though all hope seemed lost, Himiko's spirit appeared in her crystal ball, and pointed Amaterasu and Issun to where Oni Island would appear next in the sea: Watcher's Cape. The duo immediately left the palace grounds to stop Ninetails' plans and avenge Himiko's death.
Following Ninetails' defeat, Himiko was buried in the lake behind the palace. Amaterasu used Waterspout on the gravestones, which increased the goddess Nuregami's strength. Nuregami was then able to grant a secret Celestial Brush technique to Amaterasu: Deluge.
Sometime after Nippon was liberated of evil, Himiko's Palace was converted into a shrine dedicated to Himiko, as well as a Miko training ground, which was headed by Miko Cho. After accepting her Miko powers, Kagu decided to train at the palace under Miko Cho's guidance, since she wanted to control her powers in order to stand up to King Fury.
- Northern Land: In the storage room on the right wing of the palace.
- Sheep Zodiac statue: At the front yard of the palace, on the right, near a tree.
- Vengeance Slip: In the storage room on the right wing of the palace.
- Holy Bone M: At the backyard of the palace, on the porch
- #54: Outside of the main palace, in the dead end on the left wing of the palace.
- #55: Just behind the elevator leading to Himiko's throne room.
- Himiko's palace in Ōkamiden is inaccessible due to its prohibition of entrance for those who are not miko.