Takiyama Castle is spread out over a mountain ridge overlooking the confluence of the Tamagawa and Akigawa Rivers. It was built in 1521 by the Oishi family, one of the principal families of what is now the western part of Tokyo, but eventually it was taken over by the Hojo clan of Odawara, which had expanded into the Kanto Plain from the beginning of the 16th century.
In 1569 the army of Takeda Shingen of Kai province (Yamanashi) attacked Takiyama as part of its campaign against Odawara, but had to give up after a two-day battle. Eventually the Hojo built Hachioji Castle to guard the Kobosatsu Pass between Kai and the Kanto, and Takiyama was abandoned.
The castle was built with many defensive features, such as box gates and paths which could be easily defended. Even though there are no original buildings left, the layout of the spectacularly steep cuts and wide enclosures remains.