The Fujimi-yagura Keep, which was destroyed in a great fire in 1657, was reconstructed in 1659. The three-story keep stands about 16 meters high and possesses a beautiful exterior built to appear to be the same shape regardless of the angle from which it is viewed, prompting its nickname gEight-sided Keeph. After being damaged in the Great Kanto Earthquake of 1923, the structure was repaired and assumed its current form. Distinguished by their extensive use of broken natural stone, the gracefully curved walls are an early example of the uchikomihagi construction technique where rock is stacked to form a wall and then struck repeatedly with hammers to create a flat exterior surface.