Kanagawa Battery: Stone Walls and Technology beside the Opening of Yokohama

The word daiba may bring Tokyo’s Odaiba to mind. The setting here, however, is Kanagawa in Yokohama. The two sites differed in location and construction history, even though both belonged to the history of coastal batteries. Confusing them can also produce mistaken claims about materials or foundations.

The Yokohama archaeological center’s explanation places the beginning of the Shinagawa battery works in 1853–1854. Kanagawa Battery was built after Yokohama opened. Their defensive settings were related, but neither the dates nor the circumstances should be merged into one project with one uniform sequence.

The official Tokyo park history describes the designation of the third and sixth Shinagawa batteries as national historic sites in 1926 and the opening of the third as a park in 1928. That is a separate preservation history. A photograph of the Tokyo park cannot serve as a photograph of Kanagawa Battery.

Yokohama City explains that the shogunate ordered Iyo Matsuyama domain to build the battery, using a design attributed to Katsu Kaishu. Naming the designer is useful, but it does not exhaust the history of construction. The institution ordering a project and those responsible for carrying it out occupy different roles.

Stone had to be assembled by the shore, earth placed behind it and the facility brought into shape. Such work required people and materials, not simply a finished drawing. Considering those tasks connects the shogunal order with the domain responsible for construction, without claiming to reconstruct individual workers’ experiences.

A 2017 prefectural archaeology lecture document, presented by a Yokohama Board of Education lecturer, identifies Iyo Matsuyama as the construction domain and lists stone walls and approach roads among the remains investigated. Design attribution, responsibility for building and the particular objects confirmed by excavation answer related but separate questions.

What stone was used in the walls? The Yokohama archaeological center explains that andesite from the Manazuru Peninsula was used predominantly at Kanagawa Battery. Looking only at the finished wall can conceal the work needed to obtain the material before it could become part of a coastal structure.

The stones were not all supplied from within the battery’s own footprint. Their use points toward connections between a producing region and a building site. This is a material dimension of coastal defense: the facility depended on supplies reaching the place where the wall and earthworks were being assembled.

Hakone Geopark’s quarry explanation describes wedge holes on the coast and the history of andesite production, including different names associated with peninsula and inland stone. That regional context does not identify every battery block’s exact quarry or prove a complete transport route. A broader quarry history and an individual stone’s provenance remain different claims.

Two approach roads extended from the battery toward the land, one on the east and one on the west. They formed connections through which people and materials could reach the main installation. The battery should not be imagined solely as a detached island without working links to the shore.

Investigations of the western approach confirmed parts associated with an interruption in the road, a bridge and a water passage. Those observations concern particular portions of the approach. The route used for movement could have structural features different from those of the battery’s main body, despite belonging to the same overall facility.

The distinction has consequences for reading excavation results. A finding about the west approach does not automatically describe the entire enclosure or its foundations. Keeping the locations visible within the explanation makes the surviving evidence more informative, because each observation can be related to the part of the site it actually concerns.

Were the cannon used only for fighting? Kanagawa Battery also fired celebratory and ceremonial salutes. Its role included diplomatic ritual as well as the defense of the waters near an open port. This combination helps explain why cannon and international exchange belonged within the same coastal setting.

The archaeological bulletin also discusses the relationship with Yokohama’s foreign settlement. Management and use changed between the late shogunate and the Meiji period, so the installation should not be treated as remaining institutionally unchanged from completion to abolition. Different purposes and different moments need to be considered together.

Yokohama Customs’ 2019 leaflet describes the establishment of the Kanagawa Unjosho in 1859. This was a different facility concerned with trade and cargo administration. Its shared Kanagawa name does not make it the battery. Security, salutes and customs administration were distinct activities associated with the opening of the same port.

Kanagawa Battery was a coastal defense installation beside the newly opened Yokohama port. Its history brings together guarding foreign shipping, diplomatic ceremony, material procurement and the techniques supporting a stone wall. Those connections make the facility more than an isolated set of cannon or a surviving piece of masonry.

The former shoreline is difficult to see in the present city map alone. Considering the battery in relation to that earlier coast helps explain an era in which opening a port and defending the sea proceeded together. Neither activity needs to erase the other from the interpretation of the landscape.

The stonework offers a way to revisit the port’s opening through land and technology. Documents and buried remains make that possible, provided their dates, locations and limits remain visible. The conclusion rests on their combined contribution, without turning an unconfirmed foundation or a conceptual illustration into an established archaeological fact.