CastleMountain castle (yamajiro)Next 100 Fine Castles No. 130
What makes this castle distinctive
Takeda Shingen is said to have been born in this hilltop refuge castle.
Why?
Yogaisan was a refuge castle (tsume-jiro) that Takeda Nobutora built so his family could hold out if their residence at the foot of the hills were attacked. When an army from Suruga invaded the Kofu basin in 1521, Nobutora's pregnant wife is said to have taken shelter here and given birth to the future Shingen. A stone monument marking his birthplace stands on the summit.[1][2]
A climbing path lined with narrowed, stone-walled gates
Where
Along the trail up to the main enclosure; gate site (6) on the on-site signboards is the highlight.
What to look at
Gate sites where natural stones are stacked high on both sides to narrow the path, and the way the path keeps doubling back.
Why it's interesting
Along the route from the hillside to the summit, square gate enclosures (masugata koguchi), gates and terraces follow one after another. Kofu City describes gate site (6) as the castle's most heavily built. Climbing it, you feel how a Sengoku-period mountain castle was defended.[1]
Can you see it?
Visible from outsideOpen along the trail; numbered signboards mark the main features.
The summit enclosure and Shingen's birthplace monument
Where
The main enclosure on the summit.
What to look at
The flat rectangular area ringed by earthen banks, large stones that may have been part of a garden, and the "Birthplace of Lord Takeda Shingen" monument with calligraphy by Admiral Togo Heihachiro.
Why it's interesting
The enclosure measures about 73 m east–west and 22 m north–south. It is intriguing that a refuge castle may have had a garden. Kofu City also recommends the view of Mount Fuji from here.[1][3][4]
Can you see it?
Visible from outsideReached by a trail of about 30 minutes.
The ridge east of the main enclosure (signboards 14–18).
What to look at
A deep trench cut across the ridge leaving only a narrow earthen bridge (horikiri), continuing as a trench down the slope (tatebori).
Why it's interesting
These kept large numbers of enemies from rushing the main enclosure along the ridge behind it. At Yogaisan the trenches are deep and wide and reinforced with stonework.[1]
Can you see it?
Visible from outsideContinue east from the main enclosure; watch your footing.
At a glance for visitors
Nearest station
15 min walk from JR Kofu Station, North Exit (by bus)
Climb
Steep climb
Time neededEditors' estimate
About 1.5–2 hours from the trailhead to the summit and back, including time to look around.
Access
Open to visitors
The whole hill is a historic site, and the trail is open to walk. The Continued Japan 100 Castles stamp is not at the site but at the Kofu City Fujimura Memorial Hall in the plaza at Kofu Station's North Exit. When the hall is open, stamp inside; when it is closed, pre-stamped sheets are left in the black mailbox to the right of the main entrance.
In 1519 Takeda Nobutora built a residence at Tsutsujigasaki as his new base. The next year, 1520, he built Yogai Castle on Maruyama, the hill to the north, as a refuge castle (tsume-jiro) to hold out in an emergency. It is the bell-shaped hill behind Sekisuiji Temple, about 770 m above sea level.[1][3]
02
Historical record
Nobutora, founder of Kofu
Nobutora, who became head of the clan young, subdued the warlords who rebelled against him in Kai Province one after another and made them his retainers. He had them live around his residence, brought in merchants and craftsmen, and so founded Kofu as a town centered on the residence. Yogai Castle guarded that base from behind.[1]
03
Tradition
The story of Shingen's birth
In 1521 an army from Suruga advanced up the Fuji River into the Kofu basin. Lady Oi, Nobutora's pregnant wife, is said to have fled to Yogai Castle and given birth to the future Shingen there. Another account says he was born at Sekisuiji Temple at the foot of the hill, where a well said to have supplied his first bath and a small shrine still remain.[1][5]
04
Historical record
Sixty-two years under three Takeda lords
The castle served three generations, Nobutora, Shingen and Katsuyori, and for 62 years, until Katsuyori moved to Shinpu Castle, it formed the Takeda power base together with the residence below. Inside are a well called Suwa-sui that still holds water and a stone statue of the Takeda Fudo, set up in the late Edo period.[1]
05
Historical record
A National Historic Site since 1991
No buildings remain, but earthen banks, trenches, terraces and gate sites survive in good condition, and in 1991 the site was designated a National Historic Site under the name "Yogaisan." It is managed by Kofu City. The castle marked its 500th anniversary in 2020, and numbered signboards stand at the main features along the trail.[1][4]
Takeda Nobutora builds his residence at Tsutsujigasaki[1]
Yogai Castle is built as the residence's refuge castle[1][4]
Suruga forces invade; Nobutora's wife is said to give birth to Shingen at the castle[1]
Katsuyori moves to Shinpu Castle, ending its role as part of the Takeda base[1][7]
Designated a National Historic Site as "Yogaisan"[1][4]
Buildings and remains
The keep today
No keep was built
A Sengoku-period refuge castle that never had a keep.
The site today
The whole hill is a historic site with a trail through the woods. Earthen banks, trenches, terraces, gate sites and stonework survive, with signboards at the main features. There are no buildings.
Main buildings
Site only
Gates and buildings
Only the gate sites and the flat terraces remain.[1]
Key facts
Type
Castle
Setting
Mountain castle (yamajiro)built on a mountain; expect a climbEditorial article
Period
Medieval (c.1185–1570s)Editorial article
Keep (tenshu)
No keep was builtthe castle never had a keepEditorial article
Built by
Takeda NobutoraJapan Castle Foundation
Built
1520Japan Castle Foundation
Main lords
Tokugawa clan, Takeda clan, Katō MitsuyasuJapan Castle Foundation
National Historic Site (Yogaisan) (1991)Editorial article
Selection
Next 100 Fine Castles No. 130Japan Castle Foundation
Visiting
Access
Open to visitors
The whole hill is a historic site, and the trail is open to walk. The Continued Japan 100 Castles stamp is not at the site but at the Kofu City Fujimura Memorial Hall in the plaza at Kofu Station's North Exit. When the hall is open, stamp inside; when it is closed, pre-stamped sheets are left in the black mailbox to the right of the main entrance.
JR Kofu Station, North Exit (by bus)JR Chuo Main Line, Minobu Line
about 15 min walk · Steep climb
Take a bus from Kofu Station's North Exit for about 15 minutes to the Sekisuiji stop, then walk about 15 minutes to the trailhead. From there it is about a 30-minute climb to the summit enclosure.[2][3]
Checked: 2026-10-03
By car / parking
About 17 minutes by car from Kofu Station. Parking availability not confirmed.[2]
Checked: 2026-10-03
Grounds opening hours
Not confirmedChecked: 2026-10-03
Time neededEditors' estimate
About 1.5–2 hours from the trailhead to the summit and back, including time to look around.
Steps, slopes and footing
A roughly 30-minute climb on a mountain trail with switchbacks and stone-walled gate sites; Kofu City describes it as suited to strong walkers.[1][2][3]
Wheelchairs and strollers
As a mountain trail it is unlikely to be wheelchair-accessible (no official information confirmed).Checked: 2026-10-03
A temple at the foot of Mount Yogai. One tradition says Shingen was born here, and a well said to have supplied his first bath remains. About 5 minutes on foot from the Sekisuiji bus stop.[5][3]
The Takeda clan's base that Yogai Castle protected, now Takeda Shrine. Earthen banks, moats and gate enclosures survive in this National Historic Site. About 10 minutes by bus from Kofu Station's North Exit.[2]
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 Takeda Shingen and Nobutora, and for hikers who want to see a Sengoku-period mountain castle. You can also visit Kofu's three castle sites (Yogaisan, the Takeda residence and Kofu Castle) in one day.
What makes it interesting
Follow the numbered signboards as you climb and notice how each gate narrows the path and how the terraces step up the slope. At the top, take in the size of the main enclosure and the birthplace monument, then continue east to the ridge trenches.
Before you go
There are no buildings, and it is a genuine mountain castle with a 30-minute climb through the woods. Bring good shoes and water. The stamp is at the Fujimura Memorial Hall at Kofu Station's North Exit, not at the site, so stop there before or after.
Ways to enjoy it
Visit the Takeda residence site (Takeda Shrine) first, then climb Yogaisan to understand how the residence and its refuge castle worked together. Stop by Sekisuiji Temple at the foot too, and compare the two claimed birthplaces of Shingen.
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
Shingen's birth at the castle is a tradition; another account places it at Sekisuiji Temple below.
Kofu City gives the elevation as about 770 m, while Yamanashi Prefecture gives 775 m.
Yamanashi Prefecture says construction is "believed to have begun" in 1520.
The exact trailhead location, parking, toilets and the Fujimura Memorial Hall's hours could not be confirmed (the city's facility page could not be opened).
YasuCC BY-SA 3.0Wikimedia Commons
