Complete Guide to Iimoriyama Castle | The Charm of the Castle of Miyoshi Nagayoshi, a Sengoku Period Unifier, and a National Historic Site
What is Iimoriyama Castle?
Iimoriyama Castle is a Sengoku period mountain castle built on the summit of Mt. Iimoriyama, which is 315.9 meters above sea level, straddling Daito City and Shijonawate City in Osaka Prefecture.” mountain castles in western Japan, boasting a vast castle area of approximately 400 meters east-west and 700 meters north-south.
On April 6, 2017, it was selected as one of the “Continued Top 100 Japanese Castles” (No. 160) by the Japan Castle Association, and on October 11, 2021, it was officially designated a National Historic Site as it was the residence of Miyoshi Nagayoshi, who is considered the first unifier of Japan during the Sengoku period.
Many remains, such as baileys, moats, and earthen bridges, are still well-preserved today, making it a valuable historical site for understanding the realities of mountain castles during the Sengoku period.
History and Development of Iimoriyama Castle
Castle Construction and Early History
While there are various theories regarding the construction period of Iimoriyama Castle, it is believed to have been fully developed as a mountain castle in the mid-16th century. Iimoriyama is located on the border between Kawachi Province and as a key point connecting Kyoto and Osaka.
During the Nanboku-cho period, Kusunoki Masayuki is said to have been active in this area, and his tomb still remains in Shijōnawate at the foot of the mountain. A statue of Kusunoki Masayuki stands on the summit’ Imor history.
The Era of Miyoshi Nagayoshi
Iimoriyama Castle first appears on the historical stage when Miyoshi Nagayoshi (1522-1564) moved his base from Akutagawayama Castle to this castle in 1560. Nagayoshi was a powerful figure of the Sengoku period, expanding his influ Kinai region and Shikoku, and wielding real power within the Muromachi Shogunate.
Nagayoshi used Iimoriyama Castle as his residence, from which he oversaw the politics and military affairs of the Kinai region. Cultural activities, such as renga (linked verse) gatherings, were also held within the castle. Luis Frois’s “History visited Iimoriyama Castle, and that some of his retainers converted to Christianity.
Nagayoshi ruled the Kinai region before Oda Nobunaga’s ambition of unifying Japan, and he is considered the “first unifier of Japan in the Sengoku period.” Iimoriyama Castle, his residence, holds significant importance as a political center during the Sengoku period 1576).
After the Death of Miyoshi Nagayoshi and the Era of Oda Nobunaga
After Miyoshi Nagayoshi’s death at Iimoriyama Castle in 1564, the Miyoshi clan’s power gradually declined. Subsequently, it became part of the territory of Oda Nobunaga, who was expanding his power in the Kinai region.
Nobunaga used Iimoriyama Castle as a base for controlling Kawachi Province, but eventually, it lost its function as a castle and was abandoned. However, the castle’s remains were well-preserved and remain to this day.
Structure and Characteristics of Iimoriyama Castle
Scale and Layout of the Castle Area
Iimoriyama Castle is a mountain castle with baileys arranged along a ridge extending north and south from Iimoriyama Mountain. Its scale is approximately 400 meters east-west and 700 meters of north-south, making it one is known as one of the largest Sengoku period mountain castles in Osaka Prefecture.
The castle is centered around the main enclosure at the summit of Mt. Iimoriyama, with multiple enclosures arranged in a stepped fashion along the ridge. This structure effectively prevented enemy incursions and allowed for the securing of a vast castle area.
Arrangement of Enclosures
Numerous enclosures remain in good condition at Iimoriyama Castle. Enclosures are flat sections within the castle, used as spaces for building structures and stationing soldiers.
Centered around the main enclosure, various sizes of enclosures are arranged along the ridge, each organically connected while maintaining defensive functions. The enclosures are separated by moats and earthen bridges, demonstrating a design that enhances de.
Moats and Earthen Bridges
Moats are dry moats dug to cut across the ridge, and are important defensive structures that hinder enemy advances. Iimoriyama Castle retains several moats, and their scale and placement demonstrate the high level of castle-building technology during the Sengoku
Dobashi (earthen bridges) are bridge-like passages constructed by piling up earth to cross moats. They served to strengthen defenses by limiting movement routes within the castle.
Presence of Stone Walls
One of the major features of Iimoriyama Castle is that it features stone walls built using the nozurazumi (rough-stone masonry) technique, predating those of Azuchi Castle. Nozurazumi is a stone wall construction technique that involves an important example of early Sengoku period stone wall technology.
Stone walls were used in many of the baileys and can still be seen today. Considering that Oda Nobunaga built Azuchi Castle in 1576, the stone walls of Iimoriyama Castle were built earlier, demonstrating its advanced status a
Highlights of Iimoriyama Castle
Main Enclosure (Honmaru) Area
Located at the summit of Mount Iimoriyama, the main enclosure was the central part of the castle where the lord resided and conducted administrative affairs. Currently, a statue of Kusunoki Masayuki stands here, offering magnificent views. From here the Kyoto area and the Kawachi Plain.
Remains of stone walls can be seen around the main enclosure, allowing you to imagine the castle’s former grandeur.
Stone Wall Remains
The stone walls remaining throughout the castle grounds are one of Iimoriyama Castle’s greatest highlights. Built using the Nozurazumi technique, these walls showcase the skillful combination of natural stones and the techniques of the Sengoku period.
Particularly well-preserved stone walls allow for detailed observation of the stonework techniques of the time, making them valuable resources for castle research.
Remains of Moats and Earthen Bridges
Walking through the castle grounds, you’ll encounter the remains of large moats cutting across the ridge and earthen bridges crossing them. These defensive structures tell the story of how mountain castles in the Sengoku period were prepared for at
The depth and width of the moats, and the placement of the earthen bridges, offer insights into the castle’s defensive strategy, making them a must-see for castle enthusiasts.
Group of Enclosures
The group of enclosures, stretching north and south, are remnants that truly convey the scale of Iimoriyama Castle. Each enclosure had a different role, forming a single defensive system as a whole.
Hiking along the trails while exploring the enclosures allows you to experience the overall structure of the castle.
Access to Iimoriyama Castle and Hiking
Access Method
The nearest stations to Iimoriyama Castle are Shijonawate Station or Nozaki Station on the JR Gakken Toshi Line. From the station, walk to the trailhead and then take the hiking trail to the summit.
There are multiple trailheads, and you can climb from both the Shijonawate City side and the Daito City side. The time required from the trailhead to the summit is approximately 40 minutes to 1 hour.
Hiking Course
Currently, the Iimoriyama Castle ruins are maintained as the Iimoriyama Hiking Course, and many hikers visit. The course is relatively well maintained, but because you will be walking on the undulating terrain typical of a mountain castle, comfort
Information boards are installed along the course, allowing you to view the main remains while reading explanations.
Precautions for Visiting
Iimoriyama Castle is a mountain castle, and there are steep slopes and stairs. Particular caution is needed during and after rain, as the ground can become slippery.
In summer, don’t forget insect repellent, and in winter, don’t forget warm clothing. Also, there are no vending machines on the mountain, so it is recommended to prepare drinks in advance.
Designated as one of the Continued Top 100 Korean Castles and a National Historic Site
Selection as one of the Continued Top 100 Korean Castles
On April 6, 2017, Iimoriyama Castle was selected as one of the “Continued Top 100 Japanese Castles” by the Japan Castle Association. Its selection number is 160.
The Continued Top 100 Korean Castles are castles selected following the existing Top 100 Korean Castles, based on criteria such as historical value and the state of preservation of the remains. Iimoriyama Castle’s selection signifies widespread recognition of main
It is also popular among castle enthusiasts as a target for stamp rallies, attracting many visitors.
Designated as a National Historic Site
On October 11, 2021, the Iimoriyama Castle ruins were officially designated as a National Historic Site. This designation, based on the Cultural Properties Protection Law, signifies recognition as a site of significant historical value by the nation.
The designation as a national historical site is expected to further enhance the protection and development of the castle ruins. Shijonawate City and Daito City have jointly formulated a preservation and utilization plan, and are promoting appropriate preservation, management, and public access.
이모리야마 성과 미요시 나가요시
About Miyoshi Nagayoshi
Miyoshi Nagayoshi (1522-1564) was a Sengoku period daimyo from Awa Province (present-day Tokushima Prefecture). Born as the son of Miyoshi Motonaga, a senior retainer of the Hosokawa clan, he rose to prominence at a young
Nagayoshi expanded his power in the Kinai region and seized real power within the Muromachi Shogunate. While supporting the Shogun, he reigned as the de facto ruler, controlling Settsu, Kawachi, Yamashiro, Tanba, and Awa provinces.
Evaluation as a Ruler of Japan
Miyoshi Nagayoshi has recently been re-evaluated as the “first ruler of Japan in the Sengoku period,” preceding Oda Nobunaga. Before Nobunaga declared his ambition to unify Japan, Nagayoshi had already unified the Kinai region and seized control of the govern
Nagayoshi’s rule, based at Iimoriyama Castle, can be considered a precursor to the later unification of Japan by Nobunaga and Toyotomi Hideyoshi. However, because the power of the Miyoshi clan rapidly declined after Nagayoshi’s death, his achiements
Aspects as a Cultural Figure
Nagayoshi was known not only as a military commander but also as a cultural figure. He held linked verse gatherings at Iimoriyama Castle and interacted with cultural figures of the time.
He also showed a tolerant attitude towards new cultures, such as accepting Christian missionaries. Luis Frois’s records detail the missionary activities at Iimoriyama Castle.
Archaeological Excavations and Research of Iimoriyama Castle
Recent Academic Research
Continuous archaeological excavations are being conducted at Iimoriyama Castle by Shijonawate City and Daito City. Recent investigations have gradually revealed the castle’s structure, its evolution, and the technologies used.
In particular, investigations of the stone walls have shed light on the actual state of stone wall technology prior to Azuchi Castle, providing important insights into the history of castle construction technology during the Sengoku period.
New Discoveries
Excavation surveys have uncovered numerous previously unknown baileys and remains. Furthermore, unearthed artifacts are revealing details about life within the castle and the realities of trade at the time.
The discovery of Chinese ceramics and Christian-related artifacts supports the idea that Iimoriyama Castle was also a center of international exchange.
Progress in Research
Detailed layout surveys (investigations of the castle’s structure) by castle researchers are progressing, gradually revealing the overall picture of Iimoriyama Castle.
These research findings have been published in academic papers and reports, becoming important resources for the study of mountain castles during the Sengoku period.
Engagement with the Local Community
Initiatives by Shijonawate City and Daito City
Because Iimoriyama Castle spans both Shijonawate City and Daito City, the two cities are cooperating in its preservation and utilization. The two cities have jointly formulated a historical site development plan and are proceeding with the installation of information boards and the development of hiking trails.
The Cultural Properties Division, in particular, regularly holds guided tours and lectures, disseminating information to local residents and castle enthusiasts.
As a Local Historical Resource
Iimoriyama Castle is positioned as an important historical resource for the region. It is also used as an educational site for learning local history, and is featured in local history lessons at elementary and junior high schools.
Furthermore, it is attracting attention as a tourist resource, and is a place visited by history enthusiasts and castle fans from all over the country.
Volunteer Guide Activities
Guided tours are also conducted by local volunteer guides. Listening to explanations from guides knowledgeable about local history allows visitors to gain a deeper understanding of the history and charm of Iimoriyama Castle.
Guided tours are often by reservation only, so if you wish to participate, we recommend contacting the cultural property department of Shijonawate City or Daito City.
Nearby Historical Spots
Mausoleum of Kusunoki Masayuki
At the foot of Mt. Iimoriyama in Shijonawate is the mausoleum of Kusunoki Masayuki. Masayuki was a samurai during the Nanboku-cho period and is known as the eldest son of Kusunoki Masashige. This historical site, thewa is carefully preserved by the local community.
Nozaki Kannon (Jigenji Temple)
At the foot of the mountain on the Daito City side is Jigenji Temple, affectionately known as Nozaki Kannon. This temple has attracted the faith of ordinary people since the Edo period, and Mt. Iimoriyama can be seen from its grounds.
Shijonawate Shrine
Shijonawate Shrine, which enshrines Kusunoki Masayuki, is also nearby. This shrine, founded during the Meiji era, is beloved by the local community.
The Four Seasons of Iimoriyama Castle
Spring at Iimoriyama Castle
Spring is a beautiful season with cherry blossoms and lush greenery. It’s an ideal time for hiking, attracting many climbers. The temperature is mild, making it perfect for exploring the castle ruins.
Summer at Iimoriyama Castle
Summer brings lush greenery and cool shade. However, temperatures are high and insects are abundant, so adequate heat and insect protection is necessary. Early morning hikes are recommended.
Autumn at Iimoriyama Castle
Autumn is the most popular season, with beautiful autumn foliage. The weather is mild, making it suitable for long walks. The stone walls and baileys viewed through the autumn leaves have a special charm.
Winter at Iimoriyama Castle
Winter offers clear air and excellent views. On a clear day, you can see far into the distance, imagining the scenery seen by the warlords of the Sengoku period. However, warm clothing is essential. ## Tips for Enjoying Iimori
Recommended Prior Study
Having some basic knowledge about Miyoshi Nagayoshi and the history of the Sengoku period before visiting Iimoriyama Castle will allow you to enjoy it more deeply. Detailed information about Iimoriyama Castle is available on the websites of Shijonawate City and Daito
How to View the Ruins
When viewing the ruins such as stone walls and moats, paying attention to their structure and arrangement will help you understand the castle-building techniques and defensive ingenuity of the Sengoku period. Read the explanations on the information boards careful
Photography Tips
There are many photo opportunities, including stone walls, baileys, and scenic views. The view from the main bailey is particularly magnificent, offering a panoramic view of the Osaka Plain. Because it shows different expressions depending on the season and time time you visit.
Plan According to Your Physical Fitness
Iimoriyama Castle is a mountain castle and requires a certain level of physical fitness. Plan your visit according to your own physical capabilities. We recommend taking your time and strolling around at a leisurely pace, taking breaks as needed.
Summary
Iimoriyama Castle is one of the largest mountain castles in western Japan, having served as the residence of Miyoshi Nagayoshi, the first unifier of Japan during the Sengoku period. The vast castle grounds, spanning 400 meters east-west and 7 well-preserved baileys, moats, earthen bridges, and stone walls that predate Azuchi Castle.
Its historical value has been widely recognized, having been selected as one of the Continued Top 100 Korean Castles in 2017 and designated a National Historic Site in 2021. Recent archaeological excavations and research have gradually revealed an important position in the study of Sengoku period mountain castles.
Currently, it is maintained as an Iimoriyama hiking course, making it easily accessible not only to history enthusiasts but also to general hikers. Shijonawate City and Daito City are cooperating in its preservation and utilization, carefully protecting it as.
Standing on the mountaintop overlooking the Osaka Plain, and exploring the remains such as stone walls and baileys while imagining the view seen by warlords of the Sengoku period, evokes a sense of historical romance. Be sure to visit Iimoriyama Castle at yourself.