Koriyama Castle Ruins

Kōriyama Castle Ruins: A Toyotomi Stronghold Built from Borrowed Stone

On the northern face of the keep base at Kōriyama Castle, a stone Jizō figure sits wedged into the masonry upside down, its carved features turned toward the ground. Local people call it the Sakasa Jizō, the "inverted Jizō," and it is one of the more startling sights at a castle whose walls were assembled, in part, from whatever sturdy stone the builders could find. Buddhist statues, the foundation stones of dismantled temples, five-ring memorial pagodas, and even a footing said to have come from the Rajōmon gate of the ancient Heijō capital were all pressed into service. The result is a fortress that carries fragments of older Nara inside its own structure.

The castle stands at the southern tip of the Nishinokyō hills, on the western edge of the Nara Basin in the city of Yamato-Kōriyama. In November 2022 the central grounds were designated a National Historic Site, recognition that arrived more than four centuries after the site reached its peak as a center of political power.

From Tsutsui to Toyotomi to Yanagisawa

The castle's documented history begins in 1580, when the warlord Tsutsui Junkei took control of the site and began building in earnest. The transformation that made Kōriyama matter came five years later. In 1585 Toyotomi Hidenaga, younger brother of the national unifier Toyotomi Hideyoshi, entered the castle as lord of a vast domain spanning the provinces of Yamato, Izumi, and Kii, an estate assessed at roughly one million koku of rice. Hidenaga rebuilt Kōriyama on an ambitious scale and ran it as the administrative anchor for Toyotomi authority across the Kinai region around the old capitals.

After Hidenaga died, the castle passed to his nephew Toyotomi Hideyasu and then to Mashita Nagamori, one of the senior administrators of the Toyotomi government. The outer defensive perimeter, the sōgamae, is thought to have been completed during these years.

The Battle of Sekigahara in 1600 redrew Japan's political map, and Kōriyama sat without a permanent lord for a time. In 1615 Mizuno Katsunari moved in, followed by a succession of hereditary Tokugawa retainer families, the Honda and the Matsudaira among them. In 1724 the Yanagisawa clan took the castle and held it as a domain of about 150,000 koku until the end of the feudal age. When the Meiji government dissolved the old domains, most of Kōriyama's buildings were pulled down, leaving the stone walls and moats that visitors walk among today.

Why the Ruins Earned National Protection

The 2022 designation covers the heart of the castle: the main bailey with its keep base, along with the Tokiwa, Bishamon, Genbu, Jinpo, Midori, Kirin, and stable enclosures, the firewood store, and the inner and middle moats. The protected area measures just over 162,000 square meters.

What persuaded the Agency for Cultural Affairs to list the site was the survival of large-scale stonework that lets researchers read the building methods of the Toyotomi period directly from the ground. The walls were not raised in a single style. Near the main bailey, builders stacked rough natural boulders; from the Bishamon enclosure eastward toward Jinpo, they used coarsely split blocks; and around the second bailey and the Midori enclosure they worked with cut granite. Layered into the main bailey walls are the repurposed religious stones that give Kōriyama its distinctive character. Taken together, the remains show how a Toyotomi power base was engineered, and they mark the spot that served as the political center of Yamato province through the centuries that followed.

What to Look for on a Visit

Start at the keep base, the tenshudai. The tower itself was taken apart not long after Sekigahara, and for generations scholars argued over whether a full keep had ever stood here at all. Excavation work carried out between 2013 and 2017 settled the question by uncovering the original foundation stones, confirming that a keep did rise during the Hidenaga or Nagamori years. Since 2017 an observation deck has crowned the base. On a clear day the view reaches the reconstructed Daigokuden hall of the Heijō palace, the pagodas of Yakushi-ji, the grassy slope of Mount Wakakusa, and the distant cone of Mount Miwa.

Walk the second bailey to see the reconstructed buildings. The Otemon main gate was rebuilt in 1983, the eastern corner turret the following year, and the Otemukai turret in 1987, the last funded largely by donations from local residents. A multi-bay tamon turret was reconstructed as well. In 2021 the Gokurakubashi, the bridge regarded as the formal entrance to the main bailey, was rebuilt, restoring the approach that lords once used.

Then there is the masonry itself. Hunting for the inverted Jizō on the keep base, or spotting a weathered Buddhist carving turned sideways in a wall, rewards anyone who slows down and looks closely. Kōriyama is listed among Japan's hundred best cherry-blossom sites, and in spring the grounds fill for the Yamato-Kōriyama Castle Festival, when blossoms frame the stone walls and turrets.

The Goldfish Town Around the Castle

Yamato-Kōriyama calls itself the town of goldfish and castles, and the description is literal. The area is one of Japan's major goldfish-breeding centers, and shallow farming ponds spread across the outskirts where rice paddies might otherwise be. Each August the town hosts a national goldfish-scooping championship. A small goldfish museum sits about ten minutes on foot from Kintetsu Kōriyama Station, with tanks ranging from prize specimens to the ordinary fish of summer festival stalls.

The former castle town repays an unhurried walk. Old confectioners, machiya townhouses, and renovated cafés line the streets, and the Genkurō Inari Shrine and the Konya indigo-dyeing museum lie within easy reach. The castle grounds themselves are open at all hours and free to enter, though the keep-base observation deck keeps set hours: 7:00 to 17:00 from October through March, and 7:00 to 19:00 from April through September.

Getting there is straightforward. Kintetsu Kōriyama Station is about a seven to ten minute walk from the grounds, and JR Kōriyama Station roughly fifteen minutes. From Osaka or Kyoto, the castle is well under an hour by train. A large paid car park sits on the southern side near the former third bailey.