Sakuramon Gate is the grand southern entrance to Osaka Castle’s inner bailey, the Honmaru. It burned down during the Boshin War — the 1868–1869 conflict that ended the Tokugawa shogunate — and was rebuilt in 1887 in Tokugawa-period style. Inside its masugata (a rectangular defensive courtyard enclosed by two gates, designed to trap attackers in a confined kill zone) stands the Takoishi (Octopus Stone), the largest stone in Osaka Castle at roughly 108 tons, about 5.5 meters high and 11.7 meters wide, with a surface area of around 59 square meters. It was transported from Bizen Province (present-day eastern Okayama Prefecture) in 1624. Flanking the gate’s inner entrance stand the Ryū-ishi (Dragon Stone) and Tora-ishi (Tiger Stone), traditionally said to reveal their namesake shapes when wet with rain.

The Ginmeisui (“silver radiance water”) well curb originally stood near the northeast corner of the Honmaru palace kitchen and is thought to have supplied drinking water for the officials guarding the inner bailey. It was relocated to its present position in 1931, during the Main Tower’s reconstruction. The surviving stone curb and the granite paving around it are fine examples of Tokugawa-period stonemasonry. Don’t confuse this with the similarly named Kinmeisui (“golden radiance water”) well inside the Main Tower’s paid area (Spot 8) — the two wells have similar-sounding names but are in different locations and served different roles.

Inside the Sakuramon masugata stands Osaka Castle’s most famous collection of giant stones. The Takoishi (approx. 108 tons, about 5.5m high × 11.7m wide, ~59㎡) is the largest stone in the castle; the Furisode-ishi (~54㎡) is the third-largest. Both were set in place in 1624 (Kan’ei 1) under the direction of Ikeda Tadakatsu, the feudal lord responsible for this section of stonework. The Ryū-ishi (Dragon Stone) and Tora-ishi (Tiger Stone) flank the gate and are traditionally said to reveal their shapes on the wet stone surface after rain. These giant stones reinforced the castle’s defenses while also proclaiming Tokugawa power to everyone who passed through.

This large camphor tree is popularly known as the “Camphor Tree Planted by Toyotomi Hideyoshi” — the 16th-century warlord who built the original Osaka Castle. In reality, the tree standing here today was planted in March 1898 by Ogawa Mataji, then commander of the Imperial Japanese Army’s 4th Division. The site is a good example of how legend and modern commemorative memory overlap at Osaka Castle.

The Kinzo (Gold Storehouse) was originally a two-story building. In 1751 (Hōreki 1), the Tokugawa Shogunate converted it into its present single-story form to store gold and silver coins. A major repair followed in 1837 (Tenpō 8). Its distinctive namako-kabe (sea cucumber wall) plasterwork — alternating black tiles and white plaster seams — is both visually elegant and fire-resistant. It is designated an Important Cultural Property.

The Osaka Castle Toyotomi Stone Wall Museum displays a stone wall from Toyotomi Hideyoshi’s Osaka Castle. The buried wall was first discovered during a 1984 excavation, and the museum opened to the public in 2025. After the Summer Siege of Osaka in 1615, the Tokugawa Shogunate buried the Toyotomi-era castle under a massive layer of fill and rebuilt Osaka Castle on top of it. Inside, visitors can view the stone wall of the tsumenomaru (the innermost enclosure of the Toyotomi Honmaru) underground, through glass, with multilingual explanations. Admission is included with the Main Tower ticket, and there is no additional fee.

The Zannen-ishi (Regret Stones) are massive stones that were quarried and transported for the Tokugawa reconstruction of Osaka Castle but ultimately never used. Around 80 similar stones are displayed nearby at the Kokuinseki Hiroba (Inscribed Stones Plaza). Some of the displayed stones bear kokuinseki (carved marks) believed to be related to the daimyo lords or stonemason groups who quarried and supplied them.

The Kinmeisui Well House stands atop the komaru-dai (small-keep platform) and protected a vital emergency water source in case of a siege. During the Tokugawa period the well was known as Ōgon-sui (“golden water”), a name traditionally said to have later become fixed as Kinmeisui (“golden radiance water”). Dismantling repairs in 1969 established that the current structure was built in 1626. The well’s depth is recorded differently across sources — one calculation, based on the historical document Ōsaka Chikujō Chōba Wari-zu (a construction-assignment map from the castle’s rebuilding), puts it at approximately 37.72 meters. Given its elevated position on the platform, this represents a remarkable feat of engineering. The Kinmeisui Well House lies along the route up to the small-keep platform after entering the Main Tower — viewing it up close requires a Main Tower admission ticket.

The Osaka Castle Main Tower is the iconic symbol of Osaka. It is the third iteration of the castle’s keep, rebuilt in 1931 with donations from Osaka’s citizens. It now operates as an 8-floor museum covering the life of Toyotomi Hideyoshi and the history of Osaka Castle, and its exterior is modeled on the opulent main tower of the Toyotomi era. The building was registered as a national Tangible Cultural Property in 1997 and further designated an Osaka City Tangible Cultural Property in 2025.