(Translated by Google) Arrive at Shiroike Shinsui Park in about 20 minutes on foot from Nirayama Station. If you are driving, you can park at the Egawa residence or the parking lot on the north side of Shinsui Park, and the entrance to the castle that leads to Sannomaru is right there. However, if you want to see the remains of Horikiri and other structures, we recommend walking from the station.
To go to the castle ruins and water park on foot, just follow the information board. As you walk up the slope beside the junior high school, you will come to a cut-off that is closed to vehicles. Actually, this is Horikiri. After passing through Horikiri, you will arrive at Shiroike Shinsui Park.
Furthermore, if you turn left according to the information board, you will soon see Horikiri on your left. If you go up the stairs further ahead, you will come across a Horikiri with a sign that says "Horikiri 3". If you go north along the mountainside, you will come to the Sannomaru castle entrance and the parking lot, so if you head directly from the parking lot, you will not be able to see these ruins. Additionally, there are ruins of a moat surrounding the east side of Sannomaru in the parking lot, but there are no information boards, so be careful not to overlook it.
The slope leading from the castle entrance to Sannomaru bends to the right, making it look like a ``slope square''. Sannomaru is a tennis court. The top of the earthwork on the right after climbing the slope may be a turret platform.
If you follow the information board, you will arrive at Gongen Kuruwa, where Kumano Shrine is located, at the end of the earthwork opening (toraguchi). You can also head here directly from the water park. It is surrounded by earthworks, and there is a shrine on the platform on the water park side. There may have been some kind of castle facility, as it has a large area.
There is also a Horikiri between Gongen Kuruwa and Ninomaru. If you follow the road, you will reach Ninomaru. It is a large area surrounded by earthworks, so major facilities may have been located here. The earthworks on the north and south sides are widely leveled, and could they have been used as turrets?
Between the Ninomaru and the Honmaru there is a trench and a buried earthen bridge.
Climb the stairs at the end of the trench to reach the main enclosure, the highest point. It's a small place, but the view is good. It is said that you can also see Mt. Fuji from here.
Nirayama High School at the foot of the mountain is the remains of a residence. The main entrance is near the main gate of the high school. The current castle ruins are small, but in the past it was a magnificent castle surrounded by double and triple moats. There are also forts built nearby, making it a wide-area group of forts centered around the main castle, and it's fun to imagine what it might have looked like in days gone by.
In general, the earthworks and trenches are well preserved, but the signs and explanation boards are not very well maintained, so unless you have some prior knowledge, you won't be able to figure it out. It's a shame because I would have enjoyed it more if it had information about the excavation results and characteristics. One of the sacred places for Hojo fans. I hope they can improve it a little more.
(Original)
韮山駅から徒歩20分ほどで城池親水公園に到着。車なら江川邸か、親水公園北側の駐車場に停めれば三の丸に続く登城口はすぐだ。しかし、堀切などの遺構を確認したいなら、駅から徒歩で向かうことをお勧めする。
徒歩で城址や親水公園へ向かうには案内板通りに進めば良い。中学校の脇の坂道を進むと車両通行止めの切り通しに出る。実はここが堀切だ。堀切を抜けると城池親水公園に到着。
更に案内板通りに左に折れると程なく左手に堀切を確認できる。更に先の階段を登ると、「堀切3」と書かれた看板のある堀切に出会える。山際を北に進めば三の丸の登城口と駐車場に出るので、駐車場から直接向かうとこれらの遺構は確認できない。また、駐車場先に三の丸の東側を巡る堀跡があるのだが、案内板もないので見過ごしに注意しよう。
登城口から三の丸に至る坂道は右に折れていて、「坂枡形」のような様子になっている。三の丸はテニスコートとなっている。坂道を登り切った右手の土塁上は櫓台かもしれない。
案内板に沿って進むと土塁の開口部(虎口)先に熊野神社のある権現曲輪に出る。ここへは親水公園から直接向かうこともできる。周囲を土塁が囲み、親水公園側の壇上に神社がある。まとまった広さがあるので何らかの城の施設があったのかもしれない。
権現曲輪と二の丸間にも堀切がある。道に沿って行けば二の丸に至る。周囲を土塁で囲まれた広い場所なのでここに主要な施設があったのかもしれない。南北の土塁は広く削平されていて、櫓でもあったのだろうか?
二の丸と本丸間には堀切と埋もれて高さが無い土橋がある。
堀切先の階段を登れば最高地点の本丸に出る。こじんまりとした場所だか、眺めが良い。ここから富士山も望めるとのこと。
麓の韮山高校は居館跡。高校の正門付近は大手口だ。現在の城址はこじんまりしているが、往時は二重、三重の堀に囲まれた壮大な城だったとのこと。付近に砦も設けて、本城を中心とした広域の城砦群であり、ありし日の姿をここで妄想するのも面白い。
総じて土塁や堀切などがよく残っているが、表示や解説板はあまり整備されていないので予備知識が無ければピンと来ないだろう。発掘成果や特徴など記載されたものがあればもっと楽しめるのにとても惜しい。北条氏ファンなら聖地の一つ。もう少し工夫してもらえたらと期待する。