Complete Guide to Osaka Castle: Japan’s Largest and Most Famous Castle, Spanning the Toyotomi and Tokugawa Eras to the Present Day
Osaka Castle, located in Chuo-ku, Osaka City, Osaka Prefecture, is one of Japan’s most representative castles. While known as the magnificent castle built by Toyotomi Hideyoshi, most of the remains visible today date from the reconstruction by the Tokugawa Shogunate. Designated a National Special Historic Site and possessing numerous Important Cultural Property buildings, this castle can be said to embody the very essence of Japanese history.
Table of Contents
This article comprehensively explains everything you need to know before visiting Osaka Castle, from its overview to detailed history, structure, remains, cultural properties, and access information.
Overview
Osaka Castle is located at the northern edge of the Uemachi Plateau, built on a strategic location overlooking the Kawachi Plain of the Yodo River system. It is also known as “Kinjo” (錦城), a name derived from its magnificent and opulent appearance.
Osaka Castle Park currently boasts a vast area of approximately 106 hectares, and at its center stands the Osaka Castle keep, which was rebuilt in 1931 through donations from citizens. While this keep is modeled after the keep of the Toyotomi era, the stone walls on which it stands date back to the Tokugawa period, creating a unique landscape where different eras intersect.
The castle area is designated a National Special Historic Site, and many of the ancient structures, such as turrets and gates, are protected as Important Cultural Properties. It is a symbol of Osaka, attracting many tourists throughout the year, and is also known as a famous cherry blossom viewing spot.
History and Background
The history of Osaka Castle can be divided into three major periods. In each period, it was built and renovated by different rulers for different purposes.
Ishiyama Honganji Period (1496-1580)
The predecessor of Osaka Castle was Ishiyama Honganji (Osaka Honganji), a center of the Jodo Shinshu sect of Buddhism. In 1496 (Meiō 5), Rennyo established a branch temple in this area, and in 1532 (Tenbun 1), Shōnyo moved the head temple from Yamashina Honganji to Ishiyama Honganji.
Ishiyama Honganji was not merely a religious facility, but a formidable fortress surrounded by moats and earthen ramparts. During the Ishiyama War, which lasted from 1570 (Genki 1) to 1580 (Tenshō 8), it fiercely resisted Oda Nobunaga’s forces for ten years. This prolonged resistance demonstrated the geographical advantage of the location.
Ultimately, Kennyo made peace with Nobunaga and retreated to Kishū, but this strategically strong location would later catch the eye of Toyotomi Hideyoshi.
Osaka Castle during the Toyotomi Era (1583-1615)
After seizing power following the Honnō-ji Incident, Toyotomi Hideyoshi began construction of a new castle in August 1583 on the site of Ishiyama Hongan-ji Temple. Hideyoshi moved Ikeda Tsuneoki to Ōgaki and decided to make this his base of operations.
The construction was massive, involving the mobilization of daimyo from across the country. Around 1585, the main keep and the second bailey were completed. The completed keep was five stories high, lavishly decorated with black plaster and gold ornaments. It surpassed Azuchi Castle in scale and splendor, becoming a symbol of Hideyoshi’s power.
However, after being appointed Regent (Kanpaku), Hideyoshi himself moved his government offices to Jurakudai in Kyoto, and after retiring as Taiko (Regent), he conducted political affairs at Fushimi Castle, meaning he was rarely present at Osaka Castle. Nevertheless, he maintained its role as a symbol of authority, receiving New Year’s greetings from various daimyo (feudal lords) at Osaka Castle.
After Hideyoshi’s death, the Toyotomi family was destroyed in the Summer Siege of Osaka in 1615, and Osaka Castle fell and burned down. This battle resulted in the complete loss of the magnificent castle from the Toyotomi era.
Osaka Castle under the Tokugawa Era (1620-1868)
After the Siege of Osaka, Osaka Castle became a direct territory of the Tokugawa Shogunate. In 1620, the second Shogun, Tokugawa Hidetada, began large-scale reconstruction work. This reconstruction was thorough, involving completely filling in the Toyotomi-era castle and building a new one on top of it.
The Tokugawa shogunate constructed a mound of earth several meters high to seal the remains of the Toyotomi era deep underground. As a result, the stone walls from the Toyotomi period remain buried underground, and have been partially confirmed through archaeological excavations.
Construction continued during the reign of the third shogun, Tokugawa Iemitsu, in 1624, and the five-story keep was completed in 1629. This Tokugawa-era keep differed from the Toyotomi-era keep, being a magnificent structure with a layered tower design. However, it was destroyed by lightning in 1665 and was never rebuilt.
Throughout the Edo period, Osaka Castle housed an Osaka Castle Warden, functioning as an important base for monitoring the various daimyo of western Japan. The Osaka Castle Warden was a position second only to the Roju (senior councilor) and was selected from among the fudai daimyo (hereditary vassals).
From the Meiji Restoration to the Present
After the Meiji Restoration, Osaka Castle came under the jurisdiction of the army, and many buildings were demolished or destroyed by war. During the Boshin War of 1868, many buildings were lost to fire.
From the Meiji era to the early Showa era, military facilities such as the Osaka Arsenal were constructed within the castle grounds. During air raids in World War II, these facilities became targets, causing significant damage to the surrounding area.
In 1928, at the suggestion of the then-mayor of Osaka, Hajime Seki, a plan to reconstruct the castle tower began. With donations from citizens, a reinforced concrete reconstruction tower was completed in 1931. While modeled after the tower of the Toyotomi era, the interior was renovated to function as a museum.
After the war, development progressed as Osaka Castle Park, and in 1997, a large-scale renovation was carried out, known as the “Great Heisei Renovation.” Even in the Reiwa era, continuous preservation and repair work continues, with efforts being made to pass on its value as a cultural asset to future generations.
Structure
Osaka Castle has a concentric layout with a triple-layered structure: the Honmaru (main enclosure), Ninomaru (second enclosure), and Sannomaru (third enclosure) from the center outwards.
Honmaru (Main Enclosure)
The Honmaru is the central part of the castle and is currently a plaza of approximately 6 hectares surrounded by stone walls. The castle tower and Honmaru Palace once stood here. The stone walls from the Tokugawa period reach heights of over 30 meters in some places, and their sheer scale is impressive.
The Honmaru’s stone walls utilize numerous massive stones, including some with names such as “Takoishi” (Octopus Stone) and “Higoishi” (Higo Stone). These stones were transported from islands in the Seto Inland Sea, demonstrating the advanced civil engineering technology of the time.
Ninomaru and Sannomaru (Second and Third Enclosures)
The Ninomaru is the area surrounding the Honmaru, and many important cultural properties remain there today. The Senkanyagura, Tamonyagura, and Inuiyagura are representative examples.
The Sannomaru is an even outer section, corresponding to most of the current Osaka Castle Park. While development since the Meiji era has drastically altered its appearance, some parts of the moats and stone walls retain their original form.
Moats and Water Systems
The vast moats played a crucial role in the defense of Osaka Castle. A triple moat system—the inner, middle, and outer moats—surrounded the castle, stretching for several kilometers in total.
The inner moat, which still remains today, is 50-70 meters wide and reaches depths of over 10 meters in some places, a testament to the sheer scale of its excavation with the technology of the time. The moat’s water was drawn from the Yodo River system, demonstrating a design that also considered the advantages of water transport.
Changes in the Castle Tower
The castle tower during the Toyotomi period was five stories high, with a magnificent exterior featuring black plaster and gold leaf decorations. After being destroyed in the Siege of Osaka, the Tokugawa shogunate rebuilt the tower. It was a five-story, five-level structure with one basement level, featuring a dignified exterior primarily composed of white plaster.
The current reconstructed castle tower is a replica of the Toyotomi-era tower, standing approximately 55 meters tall and constructed of eight reinforced concrete. While its exterior replicates the splendor of the Toyotomi period, the stone walls upon which it stands date back to the Tokugawa period, symbolizing the layered history of the castle.
Remains
Most of the remains visible at Osaka Castle today date from the Tokugawa period onward. The remains from the Toyotomi period are buried underground, with only a portion confirmed through archaeological excavations.
Existing Structures
Osaka Castle has 13 existing buildings designated as Important Cultural Properties.
Watchtowers
- Sengan Yagura: An important watchtower protecting the main gate.
- Inui Yagura: A two-story watchtower located in the northwest corner.
- Ichiban Yagura and Rokuban Yagura: Watchtowers remaining on the south side of the second bailey.
- Kinzo: A storehouse where the shogunate’s gold and silver were stored.
Gates
- Otemon: A massive Korean-style gate serving as the main entrance.
- Sakuramon: The gate leading to the main bailey.
- Aoyamon: The gate at the rear entrance.
Tamon Yagura
- Tamon Yagura: A long watchtower standing above the Otemon.
These structures were built from the early to mid-Edo period and are valuable cultural assets that convey the architectural techniques of that time.
Stone Walls
The stone walls of Osaka Castle were built by the Tokugawa shogunate during its reconstruction, with the mobilization of daimyo from all over the country. The sections each daimyo (feudal lord) was responsible for can still be identified, and the construction methods and markings on the stone walls allow us to estimate which daimyo built which section.
The stone walls utilize advanced techniques such as “uchikomi-hagi” (a type of stonework) and “kirikomi-hagi” (another type of stonework), and remain remarkably strong even after nearly 400 years. The stone walls of the main keep, in particular, are among the largest and most impressive in Japan, representing the pinnacle of castle architecture.
Underground Remains from the Toyotomi Period
Since 1959, several archaeological excavations have uncovered Toyotomi-era stone walls and moats buried underground. The Toyotomi-era stone walls beneath the main keep are well-preserved, and a portion of them is open to the public.
These excavation results are gradually revealing the scale and structure of Osaka Castle during the Toyotomi period, and research continues to this day.
Major Boulders within the Castle
The stone walls of Osaka Castle utilize remarkably large boulders. These are known as the “Seven Boulders of Osaka Castle” and awe-inspiring to visitors.
Takoishi (Octopus Stone)
Located to the right of the main entrance to the castle grounds, directly opposite the Sakuramon Gate, this massive stone is the largest in Osaka Castle, with a surface area of approximately 36 tatami mats (about 60 square meters) and an estimated weight of approximately 130 tons. Its name comes from the fact that the pattern on its surface resembles an octopus. It is believed that this stone was transported from Bizen Province (Okayama Prefecture).
Higoishi (Higo Stone)
Located to the left of the Sakuramon Gate, this massive stone has a surface area of approximately 23 tatami mats and an estimated weight of approximately 120 tons. It is named after Kato Kiyomasa, the lord of the Higo domain, who is believed to have been involved in its transportation.
Furisodeishi (Kimono-shaped Stone)
This massive stone, located in the stone wall facing the southern outer moat, has a surface area of approximately 24 tatami mats. It was named for its shape, which resembles the sleeve of a furisode (long-sleeved kimono).
These massive stones were quarried from islands in the Seto Inland Sea, transported by ship, and then carried to the castle by a large number of people. It is a valuable legacy that speaks to the advanced civil engineering technology and mobilization capabilities of the time.
Cultural Properties
Numerous cultural properties are designated at Osaka Castle and its surrounding area.
Special Historic Site
Osaka Castle ruins were designated a National Special Historic Site in 1953. Special Historic Sites are limited to those of particularly importance among historic sites, and there are only 63 such sites nationwide (as of 2024). Osaka Castle is one of them, and its academic and historical value is highly regarded.
Important Cultural Properties
Thirteen buildings, including the aforementioned turrets and gates, are designated as National Important Cultural Properties. These are valuable legacies that convey the architectural techniques of the Edo period and are preserved through regular repairs.
During the major renovations in the Heisei era, the Senkan-yagura and Tamon-yagura towers were dismantled and repaired, restoring them to a state close to their original appearance.
Registered Tangible Cultural Properties
Within Osaka Castle Park, modern buildings constructed after the Meiji era also remain, some of which are designated as Registered Tangible Cultural Properties. The former 4th Division Headquarters building (now Mirai-za Osaka Castle) is an example.
These were originally built as military facilities, but are now used as cultural and commercial facilities, serving as excellent examples of the preservation and utilization of historical buildings.
Museum Materials in the Castle Tower
Osaka Castle Tower serves as a museum, housing and exhibiting numerous valuable materials related to Toyotomi Hideyoshi and Osaka Castle. These include paintings, armor, and ancient documents designated as Important Cultural Properties and Important Art Objects, and various special exhibitions are held throughout the year.
Location
Osaka Castle is located at 1-1 Osaka-jo, Chuo-ku, Osaka City, Osaka Prefecture. Located at the northern edge of the Uemachi Plateau, Osaka Castle was once a natural stronghold surrounded by rivers and wetlands.
Currently, Osaka Castle Park is an urban park located in the heart of Osaka City, accessible by multiple train lines including the JR Osaka Loop Line, the subway, and the Keihan Railway.
Besides the castle tower, the park contains facilities such as Osaka Castle Hall, a baseball field, and an archery range, making it a popular recreational spot for citizens. In spring, approximately 3,000 cherry trees bloom, making it one of the leading cherry blossom viewing spots in western Japan.
Transportation Access
Access to Osaka Castle is very convenient, with multiple modes of transportation available.
Access by Train
JR Osaka Loop Line
- Get off at Osakajo-Koen Station: Approximately 15 minutes on foot to the castle tower.
- Get off at Morinomiya Station: Approximately 15 minutes on foot to the castle tower.
Osaka Metro (Subway)
- Get off at Tanimachi 4-chome Station (Tanimachi Line/Chuo Line): Approximately 15 minutes on foot.
- Get off at Osaka Business Park Station (Nagahori Tsurumi-ryokuchi Line): Approximately 15 minutes on foot.
- Get off at Morinomiya Station (Chuo Line/Nagahori Tsurumi-ryokuchi Line): Approximately 15 minutes on foot.
Keihan Railway
- Get off at Tenmabashi Station (Keihan Main Line): Approximately 20 minutes on foot.
Access from the Airport
From Kansai International Airport
- Take the JR Kansai Airport Rapid Service or Limousine Bus to Osaka Station or Namba Station, then transfer to the Loop Line or subway. Travel time: Approximately 60-90 minutes.
From Osaka International Airport (Itami Airport)
Take a limousine bus to Osaka Station, then transfer to the Osaka Loop Line. Travel time: approximately 40-60 minutes.
By Shinkansen (Bullet Train)
From Shin-Osaka Station, take the JR conventional line to Osaka Station, then transfer to the Osaka Loop Line to Osakajo-Koen Station or Morinomiya Station. Travel time: approximately 30 minutes.
Access by Car
Approximately 5 minutes from the “Hoenzaka Exit” of the Hanshin Expressway Route 13 Higashi-Osaka Line. However, parking within the park is limited, so the use of public transportation is recommended.
Accessibility Information
Osaka Castle Park is a historical site with many steps, but some routes have ramps. An elevator is installed to the main keep, making it accessible for wheelchair users (however, it only goes up to the 5th floor; the top floor (8th floor) is only accessible by stairs).
Multipurpose restrooms are located in several places within the park, and accessibility maps are available.
Highlights of Osaka Castle
Here are some of the main sights to see when visiting Osaka Castle.
Castle Tower
Osaka Castle’s castle tower is eight stories high, with exhibition rooms on each floor. From the observation deck on the top floor, you can enjoy a panoramic view of Osaka city, and on clear days, you can even see Mount Rokko and Mount Ikoma in the distance.
The tower displays materials related to the life of Toyotomi Hideyoshi, the history of Osaka Castle, and the Siege of Osaka. Easy-to-understand explanations are provided through audio guides and touch-panel displays.
Important Cultural Property Buildings
Important cultural property buildings such as the Senkan-yagura, Tamon-yagura, and Inui-yagura are usually only viewable from the outside, but interior tours are possible on special open days a few times a year. This is a valuable opportunity to see Edo period architectural techniques up close.
Stone Walls and Giant Stones
The stone walls around the main keep are a must-see. The giant stones, such as the Takoishi and Higoishi around the Sakuramon Gate, are particularly impressive in their size. The stone walls still bear the markings of various feudal lords, making it a delightful experience to search for them as you walk around.
Plum Grove and Cherry Blossoms
Osaka Castle Park boasts a plum grove with approximately 1,270 plum trees of about 100 varieties, with the best viewing time being from late February to early March. Additionally, around 3,000 cherry trees bloom from late March to early April, making it one of the leading cherry blossom viewing spots in western Japan.
Nighttime Illumination
The castle tower is illuminated after sunset, creating a magical sight. The lighting colors sometimes change depending on the season and events, making it a popular spot for nighttime views.
Summary
Osaka Castle is one of Japan’s most representative castles, with a history of over 400 years since its construction by Toyotomi Hideyoshi. While many of the remains visible today are from the reconstruction by the Tokugawa Shogunate, remnants of the Toyotomi era lie beneath, and the reconstructed castle tower mimics the appearance of the Toyotomi period, creating a unique historical landscape where different eras intersect.
Osaka Castle, a national special historic site, a designated important cultural property, and a castle tower restored through citizen donations, possesses both cultural value and the function of a beloved park for its citizens. It will undoubtedly continue to be cherished by many as a symbol of Osaka.
The massive stones of the stone walls, the imposing turrets and gates, and the magnificent appearance of the restored castle tower convey to visitors the weight of Japanese history and the high level of skill of our ancestors. When you visit Osaka, be sure to take your time to fully appreciate the charm of Osaka Castle.