was a Japanese castle located in the city of KÃ Âfu, Yamanashi Prefecture, in the Chubu region of Japan. The site has been protected as a National Historic Site since 2019. The castle is also known as Maizuru Castle, and the present-day surroundings are called .
Kà Âfu Castle is located in the physical center of the city of Kà Âfu on a small hill. The city itself is located at the confluence of the Kamanashi River and the Fuefuki River. During the Sengoku Period after the local warlord (Takeda Shingen) seized control of the province from his father. He made Tsutsujigasaki Castle his seat. Before this time, the Kà Âfu area was subject to frequent flooding, and it was only through massive flood control projects which were undertaken by Takeda Shigen over a 20-year period that the area was considered inhabitable. After Takeda Shingen's death, his son Takeda Katsuyori was defeated by a coalition of the Oda clan and the Tokugawa clan in 1582. Oda Nobunaga placed his general Kawajiri Hidetaka in charge of Kai Province, but Nobunaga was assassinated only three months later and vengeful former Takeda clan retainers assassinated Kawajiri soon afterwards. The vacant province was fought over by Tokugawa Ieyasu and the Late Hà Âjà  clan, with Ieyasu emerging victorious. However, after the 1590 Siege of Odawara, Toyotomi Hideyoshi forced Ieyasu to exchange his holdings for new territories in the Kantà  region and gave Kai Province to his retainer Kato Mitsuyasu (1537âÂÂ1593).
Kato originally governed from the old Tsutsujigasaki palace, but as that site had minimal defenses and had little room for expansion, he began work on a new castle at Ichijyomodoriyama, a small hill a short distance away, which had a small fort guarding the valley. This was later called "Kà Âfu Castle". He died before the completion of the new castle, and was succeeded by Asano Nagamasa (1547âÂÂ1611), Hideyoshi's step-brother-in-law. Asano completed the castle in 1593.
KÃ Âfu Castle was originally T-shaped, with the main body spreading on the ridge of the hill from east-to-west, separated into three or four layers of terraces over a 200 by 100 meters area. The front of the castle protruded north-to-south and had the main gate. The inner bailey was at the top of the hill measuring 100 by 50 meters, with a four-story tenshu painted black with gold-colored roof tiles. Below the inner bailey were several enclosures with a complex system of stone walls, in some places up to 15 meters in height.
After the Battle of Sekigahara, Kà Âfu Castle came into the hands of the Tokugawa clan with whom it remained until the end of the Tokugawa shogunate. The Tokugawa shogunate initially used Kà Âfu Castle as a stronghold that the shà Âgun could retreat to, should any enemies take Edo Castle. Although the tenshu constructed by Asano Nagamasa had fallen into ruin and was not replaced, the castle itself was kept in good repair and was ruled by a cadet branch of the clan.
Tokugawa Tsunatoyo, the daimyà  of Kà Âfu, became the heir of the fifth Shà Âgun Tokugawa Tsunayoshi and moved to Edo Castle. He was replaced in 1704 by Yanagisawa Yoshiyasu, one of Tokugawa Tsunayoshi's closest retainers. Yanagisawa Yoshiyasu was also a descendant of the Takeda clan, and made strong efforts for restoring the prosperity of the region. However, his son Yanagisawa Yoshisato was transferred to Yamato Kà Âriyama Domain, and Kai province became tenryà  territory ruled directly by the shogunate though an appointed hatamoto administrator. During this period, the honmaru of the palace and the Akagenenmon gate were destroyed by a large fire in 1727.
During the Boshin War of the Meiji restoration, Katsu Kaishà « dispatched the Shinsengumi under Kondo Isami to seize Kà Âfu Castle before it could fall into the hands of the advancing Imperial army. However, the Imperial army led by Itagaki Taisuke reached Kà Âfu first and took the castle without a fight. The Imperial Army then defeated the Shinsengumi at the Battle of Katsunuma to keep the castle.
At the start of the Meiji period, the castle was abandoned, and in 1877 in accordance with government orders that all old fortifications were to be destroyed, all of the remaining castle structures were pulled down. The outer areas of the castle became the location of KÃ Âfu Station, and other areas were occupied by government offices. In 1904 the area around the inner bailey was opened to the public as Maizuru Castle Park. Since the 1990s, archaeological excavations and reconstruction of the important castle features have been ongoing, and reconstructions of the gate and a yagura tower were completed in 2004. The tower functions as a museum that features many artifacts from the castle's original buildings.
The castle is a ten-minute walk from Kà Âfu Station on the JR East Chà «à  Main Line.