Also known as the Ushigome Gateway, Ushigome-mon Gate was constructed in 1636 under the direction of Hasuchika Tadateru, the lord of Tokushima domain. As described in the Illustrated Maps of Edo Castle’s Outer Gates, Ushigome-mon Gate’s inner section was surrounded by stone walls, which were arranged in a square shape to form an enclosure. It was comprised of two gates: a Korean-style outer gate, which led to a square courtyard and could be entered from the earthen bridge, and a large, two-story inner gate containing a timber-framed gatehouse. Even if enemy forces successfully penetrated the outer gate and entered the courtyard, they were prevented from entering the castle grounds by the large internal gate. Ushigome-mon Gate’s design enabled forces defending the Castle to attack the enemy from the walkway in the gatehouse’s upper tier and positions atop the stone walls surrounding the courtyard. In 1872, the Ministry of the Army assumed control of Edo Castle and were tasked with protecting the Imperial Palace. After taking control, they announced that many of the existing gates would be torn down in the name of security. Ultimately, they order the removal of 21 of the outer gates. The Ministry of the Army then assumed responsibility for guarding and maintaining the gates that remained in place. In an effort to develop Tokyo’s urban infrastructure, the Tokyo prefectural government moved carried out the actual work of removing the castle gates, elevated walkways above the gates, stone walls that surrounded many of the gates, and the earthen fortifications in their vicinity. In 1902, after the elevated walkway above Ushigome-mon Gate had been removed a portion of the stone walls surrounding its inner sections were torn down. However, the eastern and western walls were left in place and remain in existence today. The original form of the square courtyard that surrounded the gate is indicated by the surface of the road constructed in its place. It enables visitors to grasp the layout of the square courtyard that surrounded the Gate’s inner portion. The exhibit on the first floor provides a detailed description of the stone walls’ struc-ture. A cornerstone retrieved from the side of one Ushigome-mon Gate’s stone wallsis emblazoned with two seals: those of Hachisuka lemasa and Hachisuka Tadahide, who supervised. the construction of Ushigome-mon Gate’s walled courtyard.
神楽坂（新宿区）側に残る橋台 The Remained Bridge Stage Beside Kagurazaka 1989（平成元）年の地下鉄南北線工事における発掘調査で、牛込橋の新宿区側の橋詰に高さ9.5mの牛込見附の土橋の石垣が確認されました。石垣は軟弱な地盤の下位にある強固な砂層地盤を支持層として梯子胴木を敷いた上に築かれており、弱い地盤施工する際の工夫が伺えます。その他、当時の土橋の側溝の構造がわかる遺構なども発見されています。
An archaeological excavation carried out in 1989 in conjunction with the construction of Tokyo’s Nanboku Subway Line uncovered a 9.5-meter-high stone wall from the Shinjuku Ward-side approach to Ushigome-mon Gate’s earthen bridge. The stone wall was constructed on top of a crib base, which served as a support layer for the hardened stratum of sand comprising the bottom tier of the site’s weak foundation. This discovery provides us with insight into the techniques used during the Edo period when building on sites with an unstable foundation.
