Maruoka Castle is located on top of a small hill in the plains north of the city of Fukui.

[2] Resentful that her son had not been made a samurai her spirit according to legend would make the moat overflow with spring rain when the season of cutting algae came in April every year.

People called it, "the rain caused by the tears of O-shizu's sorrow" and erected a small tomb to soothe her spirit.

As it was being sited on top of a low hill it was decided to mount the tenshu on a high stone base in order to gain additional height.

However, the Aoyama sided with the Western Army under Ishida Mitsunari during the Battle of Sekigahara and were thus dispossessed by the victorious Tokugawa Ieyasu.

Ieyasu awarded Echizen Province to his son, Yūki Hideyasu, who in turn created a 26,000 koku holding centered at Maruoka for his retainer, Imamura Moritsugu.

Due to Honda Narishige's efforts at the Siege of Osaka in 1624, the kokudaka of the domain was further raised to 46,300 koku.

The Arima clan continued to rule Maruoka for eighth generations until the abolition of the han system in July 1871 during the Meiji Restoration.

By dating the timber used in the construction of the tenshu from its rings, radiocarbon concentration, and oxygen isotope ratio, they reported after four years of investigations in March 2019 that most of the through pillars, which play a structurally important role, were cut down after 1626.

The former castle grounds are now incorporated in the Kasumigajo Park, which contain some remnants of the ramparts and moats as well as a small museum that displays some arms, armour, and household items related to its former lords.

[10] An annual cherry blossom festival is held during the first three weeks of April during which the trees are lit up in the evenings by over 300 paper lanterns.

[2] The right-hand side of the tenshu has a series of protruding ishiotoshimado (stone-dropping windows) that allowed defenders to shoot at enemies via timber slats and also via a trap door to drop stones or pour oil or boiling water on attackers underneath.