Kozenji Temple is located on the ruins of the house where Kasuga no Tsubone (Lady Kasuga) was born. She was from a prominent samurai family, which had taken the post of Shugo-dai (acting governor) of Mino Province (present-day southern part of Gifu Pref.). During the Warring States Period, the area around the temple was a castle town of Kuroi Castle located at the top of the mountain behind the town. In 1579, the castle fell as part of Akechi Mitsuhide’s operation to pacify the Tango region, after which Saito Toshimitsu, who was a retainer of Akechi Mitsuhide, moved to this place. At the end of this year, Lady Kasuga was born as Saito Fuku, a daughter of Saito Toshimitsu. After being defeated at the battle of Yamazaki, her father was captured and executed. Fuku escaped punishment for being a woman, and was brought up at Kozenji Temple, where she received strict lessons in calligraphy, poetry, incense burning, and other cultural studies needed as a court noble. This school time became the underlying basis of her later accomplishments as a wet nurse of Shogun. In the precinct are “Koshikake-iwa (sitting stone)” and “Sanba-ido (midwife well),” which remind us of Lady Kasuga in her early childhood.

The Marumou Family Lower Mansion is the symbol of Usuki, a former castle town. It was once the mansion of a high-ranking samurai who had defined its late-Edo period architectural style.

The Marumou family were samurai of the former Mino clan (in today's Gifu Prefecture), and were once in service to Mitsuhide Akechi. After Mitsuhide was defeated by Hideyoshi Toyotomi during the Battle of Yamazaki in the 10th year of the Tenshou era (1582), the family was homeless for many years.

The family made a comeback in the 5th year of the Kannei era (1628) during the Edo period. Because the first leader of the Usuki clan, Sadamichi Inaba, was related to the Marumou family, they were taken in by them. Soon after, the Marumou family came to reign as one of the highest-ranking samurai families in the Usuki clan.

One of the main characteristics of the Marumou Family Lower Mansion is that the house is completely divided by walls into several parts, including an 'omote' for guests, and an 'oku' for living quarters. Not only individual rooms but the entrance also is divided, for guests and family. One can see how seriously the samurai family took tradition and ceremonies.

The ruins of Kameyama castle (Tanpa-Kameyamajo) are located in Kameoka-shi, Kyoto Prefecture. The castle (also known as Kihoujo and Kasumijo) was founded by Akechi Mitsuhide, who was a general under the daimyo Oda Nobunaga, and who lived during the feudal Warring States period. All that remains of the castle today are some parts of the fan-shaped stone wall, the castle tower and the inner moat.

Tanpa-Kameyamajo was built in 1577 by Akechi Mitsuhide, then added to by the daimyo Toudou Takatora, during the Azuchi-Momoyama period. In 1610, he completed the front gate to the five-story main tower and an outer moat, after which the castle became known as the Kameyamajo.

In 1877, the Meiji government had the castle demolished. In 1919, the Japanese religious sect Oomoto-kyo bought the ruins and built the stone wall from the remaining stones of the ruined castle. This wall stands today.

The Kameyamajo is also notorious as the site of the Honnoji Incident. Akechi Mitsuhide, a general under Oda Nobunaga, left the castle to retaliate against Nobunaga at Honnoji, which led to the death of the great Nobunaga. It also resulted in Mitsuhide gaining power and taking over the reins of power in just three days. Indeed, these castle ruins make us ponder and daydream about the Warring States period.