CastleHilltop castle (hirayamajiro)Next 100 Fine Castles No. 141
What makes this castle distinctive
Nobunaga's stone walls crown the hill, while the double earthen walls and moats at its foot were built by Tokugawa Ieyasu's side 21 years later.
Why?
Mount Komaki has two castles in one. In 1563 Oda Nobunaga built a castle here to live in, and in 1584, during the Battle of Komaki and Nagakute, the allied forces of Oda Nobukatsu and Tokugawa Ieyasu rebuilt its ruins into a jinjiro, a temporary fortress for war. Excavations show that Nobunaga-era stone walls survive near the summit, while the double earthen walls and moats ringing the foot of the hill are Ieyasu's side's work.[2][3][6][7]
Around the main bailey (shukaku) at the summit. West of the Komakiyama History Museum is a section of wall that was visible even before the recent restoration work.
What to look at
Walls of unworked natural stone, stacked in tiers
Why it's interesting
Because Nobunaga lived here for only four years, Komakiyama was long thought to be a temporary fort for his campaign against Mino. Excavations then uncovered three tiers of stone walls ringing the summit, showing it was a full-fledged castle. One stone even bears the name "Sakuma" in ink, which Komaki City describes as the oldest known ink inscription on a castle wall stone in Japan.[8][9][6][10]
Can you see it?
Partly visibleSome walls, such as the section west of the museum, can be seen outdoors. The stone with the "Sakuma" inscription is displayed at Rekishiru Komaki (Komakiyama Castle Historical Information Center).
02
Ieyasu's earthen walls and moats around the foot
Where
The base of the hill. Near the back-gate (karamete) trail there is a display showing a cross-section of an earthen wall.
What to look at
The double ring of earthen walls and moats around the hill, the shape of the gateways (koguchi), and the cross-section of a wall
Why it's interesting
In 1584, when Hideyoshi's army took Inuyama Castle and prepared to push south, Ieyasu's side heavily rebuilt the ruins of Nobunaga's castle as its headquarters. They dug a new moat and double earthen walls all the way around the base of the hill and remade every gateway. The work of raising walls and deepening moats is said to have been finished in only about five days.[3][7][10]
Can you see it?
Visible from outsideFree to see from the walking paths. Some earthen walls were rebuilt after the old city hall moved away.
The Ote-michi, the main approach straight up the hill
Where
From the Ote-guchi (main gate) at the south foot up to the summit
What to look at
The route climbing from the main gate toward the summit
Why it's interesting
The Ote-michi was laid out when Nobunaga built the castle as its formal front approach, and excavations have found Nobunaga-era stonework along it. You can still walk up from the main gate and follow the front route of Nobunaga's castle.[10][9]
Can you see it?
Visible from outsideOpen to walk; no vehicles allowed.
At a glance for visitors
Nearest station
20 min walk from Meitetsu Komaki Station
Climb
Some climbing
Time neededEditors' estimate
About 2 hours to climb the Ote-michi to the summit and visit both the History Museum and Rekishiru Komaki.
Admission
200 yen; 100 yen for groups of 30+; free for ages 18 and under. The same ticket admits you to the Komakiyama History Museum on the summit.
Hours
9:00–17:00 (last entry to the permanent exhibition 16:30)
Access
Open to visitors
The whole hill is free to walk. No vehicles are allowed; it is about a 15-minute walk from the foot to the summit museum. The exhibition rooms of the History Museum and Rekishiru Komaki charge a fee (one ticket covers both). The Continued Top 100 Castles stamp is available at both. Drones and open fires are prohibited.
Mount Komaki is a lone hill, 85.9 m high, at the eastern edge of the Nobi Plain. After defeating Imagawa Yoshimoto at Okehazama in 1560, Oda Nobunaga was preparing to attack the Saito clan of Mino Province. He chose this hill, whose summit looks out toward Mino, built a castle in 1563, and moved here from Kiyosu Castle.[5][2][7]
02
Historical record
Nobunaga's first castle and town of his own
Komakiyama was the first castle Nobunaga built himself. South of the hill he laid out a planned castle town about 1.3 km by 1 km, with merchants and craftsmen on the west side and retainers' residences and temples on the east. Komaki City notes that this already shows the layout of the castle towns that later spread across Japan. When Nobunaga took Mino in 1567 he moved to Inabayama Castle (later Gifu Castle), and Komakiyama fell out of use.[2][4][7]
03
Historical record
Headquarters in the Battle of Komaki and Nagakute
After Nobunaga died in the Honnoji Incident of 1582, his son Oda Nobukatsu fell out with Hashiba (later Toyotomi) Hideyoshi, and in 1584 the Battle of Komaki and Nagakute broke out. Tokugawa Ieyasu came to Nobukatsu's aid, rebuilt the castle ruins on Mount Komaki as his headquarters, and lined up forts to the east to block Hideyoshi's army from moving south. There was no great battle around Komaki itself; after winning at Nagakute on April 9, Ieyasu was back at Mount Komaki by the next morning. A peace was reached in November, and the castle was abandoned again.[3][7]
04
Historical record
Protected as Ieyasu's lucky camp
In the Edo period Mount Komaki belonged to the Owari domain and was treasured as the camp where Ieyasu secured his victory; ordinary people were forbidden to enter. The Ezaki family, village headmen of Komaki, looked after it. As a result, the moats and earthen walls on the hill survived in excellent condition. Meanwhile, what remained of Nobunaga's castle town was moved east of the hill in 1623 and became today's central Komaki.[11][2][7]
05
Historical record
A National Historic Site, and bringing back the walls
Mount Komaki became a National Historic Site in 1927, and in 1930 the Owari Tokugawa family donated it to the town of Komaki. After the war a junior high school, the city hall and other buildings went up on the site and some remains were lost, but policy later shifted toward moving the facilities out and restoring the site. The Komakiyama History Museum on the summit was built in 1968 by businessman Hiramatsu Shigeru at his own expense and donated to the city; it is modeled on the Hiunkaku pavilion in Kyoto. Today, work based on the excavation results is bringing Nobunaga's stone walls back into view.[11][12][13][14]
The history museum building is completed on the summit[13]
The museum reopens as the Komakiyama History Museum with new Warring States displays[12][13]
Buildings and remains
The keep today
Mock keep
The Komakiyama History Museum on the summit is a three-tier, four-story reinforced-concrete building completed in 1968, designed after the Hiunkaku pavilion in Kyoto. It is a castle-style building, not a reconstruction of a keep from Nobunaga's castle.
The site today
The whole hill is a National Historic Site and can be explored as a wooded park. The Komakiyama History Museum stands on the summit, with Rekishiru Komaki (the castle's historical information center) and Sosuikan at the south foot. Restoration of stone and earthen walls based on excavation results is ongoing.
Main buildings
Modern reconstruction
Komakiyama History Museum
Completed in 1968, built and donated by Hiramatsu Shigeru. A castle-style building modeled on Hiunkaku, with an observation room on the 4th floor.[13]
Original
Stone walls of the main bailey
Nobunaga-era stone walls. Excavations found three tiers ringing the summit; restoration is under way.[8][6]
Original
Earthen walls and moats at the foot
Double earthen walls and moats built in Ieyasu's side's 1584 remodeling. Some sections were restored on the former city hall site.[3][10]
Original, relocatedRegistered Tangible Cultural Property
Komaki City Sosuikan
Built in 1888 as a guesthouse on the west side of the summit and moved to its present spot in 1949; restored to its original appearance in 2022. Not a castle building.[15]
Key facts
Type
Castle
Setting
Hilltop castle (hirayamajiro)built on a low hill rising from the plainEditorial article
Period
Medieval (c.1185–1570s)Editorial article
Keep (tenshu)
Mock keepa keep-shaped building where no keep existed, or where its appearance is unknownEditorial article
Built by
Oda Nobunaga, Tokugawa IeyasuJapan Castle Foundation
National Historic Site (Mount Komaki) (1927)Editorial article
Selection
Next 100 Fine Castles No. 141Japan Castle Foundation
Visiting
Access
Open to visitors
The whole hill is free to walk. No vehicles are allowed; it is about a 15-minute walk from the foot to the summit museum. The exhibition rooms of the History Museum and Rekishiru Komaki charge a fee (one ticket covers both). The Continued Top 100 Castles stamp is available at both. Drones and open fires are prohibited.
Walk about 1.9 km west from the station to the foot of the hill, then climb about 15 minutes more to the summit museum. Buses from the station's East Exit also run to Komaki Shiyakusho-mae (take one routed via city hall).[16][17][14]
Checked: 2026-10-03
Hours and admission
Rekishiru Komaki (Komakiyama Castle Historical Information Center)
Hours
9:00–17:00 (last entry to the permanent exhibition 16:30)
Closed
3rd Thursday of each month (the next weekday if it is a holiday), December 29 – January 3
Admission
200 yen; 100 yen for groups of 30+; free for ages 18 and under. The same ticket admits you to the Komakiyama History Museum on the summit.[14]
Checked: 2026-10-03
Komakiyama History Museum
Hours
9:00–16:30 (last entry to the paid area 16:15)
Closed
3rd Thursday of each month (the next weekday if it is a holiday), December 29 – January 3
Admission
200 yen; 100 yen for groups of 30+; free for ages 18 and under (shared ticket with Rekishiru Komaki)[13]
Checked: 2026-10-03
By car / parking
About 5 minutes from the Komaki IC. Parking: Komaki City Hall lot (open all day, free, 294 spaces); Komakiyama North lot (first 2 hours free, then 100 yen per 30 minutes, 50 spaces); a free bus lot (4 large buses). Search for "Komakiyama History Museum" or "Komaki City Hall" in your car navigation.[16][17]
Checked: 2026-10-03
Grounds opening hours
Not confirmedChecked: 2026-10-03
Time neededEditors' estimate
About 2 hours to climb the Ote-michi to the summit and visit both the History Museum and Rekishiru Komaki.
Steps, slopes and footing
An 85.9 m hill; about 15 minutes on slopes and steps from the foot to the summit. The back-gate route follows a zigzag path called Godanzaka.[12][10]
Wheelchairs and strollers
Not confirmedChecked: 2026-10-03
Toilets and rest
Not confirmed
English signs / audio guide
English guidance is not confirmed.
Seasons
Cherry blossoms in spring and autumn leaves in fall.[10]
Photography
No photography in Rekishiru Komaki's permanent exhibition room. In the History Museum, photos are allowed only at the 1st-floor photo spot and the 4th-floor observation room. Drones and radio-controlled helicopters may not be flown on the hill.[14][13][18]
Works, closures and restrictions
The city warns visitors to watch for fallen trees and branches on the paths.[19]Checked: 2026-10-03
An 1888 guesthouse at the south foot of Mount Komaki, restored to its original appearance in 2022 and registered as a Tangible Cultural Property in 2025. It can be toured on days when it is not booked (closed Thursdays).[15]
Checked: 2026-10-03
Editors' guide
An editorial guide based on sources and confirmed information — not a first-hand visit report.
Who will enjoy it
Good for fans of Nobunaga and Ieyasu, anyone who prefers reading a castle's story from its walls and earthworks rather than a keep, and travelers looking for a castle site within easy reach of Nagoya.
What makes it interesting
Walk with the idea that the top and the bottom of the hill belong to different eras: the stone walls near the summit are from Nobunaga's 1563 castle, and the double earthen walls and moats at the foot are from Ieyasu's side's 1584 fortress. See the "Sakuma" ink-inscribed stone at Rekishiru Komaki before you climb, and the walls will look different.
Before you go
The summit museum is not a reconstruction of an old keep but a 1968 building modeled on Kyoto's Hiunkaku. Cars cannot drive up, so you will walk from the foot. Both museums close on the 3rd Thursday of the month.
Ways to enjoy it
Climb the Ote-michi from the south main gate to follow Nobunaga's front route, then come down by the zigzag Godanzaka on the back side and past the earthen-wall cross-section, and you will see both eras' castles in one loop. From the 4th-floor observation room of the History Museum you get a 360-degree view of the Nobi Plain, including the direction of Mino that Nobunaga had his eye on.
Photos
Visitor reviews
Be the first to review
Have you visited this castle? We'd love to hear from you.
Write a review
Open questions
The Chronicle of Lord Nobunaga does not give the year the castle was built; 1563 is the accepted date based on letters and diaries of the time.
The five-day remodeling is what is said; researchers think the work focused on the walls, moats and gateways around the foot and midslope, leaving most baileys untouched.
The claim that the "Sakuma" inscription is the oldest ink inscription on a castle wall stone in Japan comes from Komaki City.
The History Museum was started in 1967 and completed in 1968 per the official site; some sources give 1967.
Accessibility information, toilet locations, English guidance and park opening hours could not be confirmed.
Yanajin33CC BY-SA 3.0Wikimedia Commons
