• Besshi Copper Mines Heritage of Industrial Modernization

    Besshi Copper Mines shaped the development of the industrial city of Niihama and the Sumitomo Group.
    Despite the closure of the mines in 1973, the physical legacy of this heritage is evident to this day in Niihama, reminding visitors of the past.

An extraordinary industrial heritage stretching 40 kilometers from the mountain to the island

A major copper deposit in Japan

Niihama City in Ehime Prefecture is part of the Seto Inland Sea Industrial Zone. The Besshi Copper Mines are located in the Akaishi Mountain Range to the south of this major city in Shikoku. When the Earth was young, this land was under the sea and mineral deposits containing copper were formed by submarine volcanic activity. This copper deposit stretching deep beneath the Earth breached the surface, breaking through the surrounding strata, awaiting discovery by human beings. 1,800 meters in length and 2.5 meters in thickness, the deposit stretches from about 1,200 meters above sea level to about 1,000 meters below sea level with an inclination of about 45 to 50 degrees and is one of the largest in Japan.

View of Niihama City and Seto Inland Sea from the Dozangoe Pass, which is the highest point of the Besshi Copper Mines
View of Niihama City and Seto Inland Sea from the Dozangoe Pass, which is the highest point of the Besshi Copper Mines
Remains of the mining town that flourished in the Edo period, where some 3,000 people lived, engaged in mining and refining.

Following the discovery in 1690 of an exposed copper vein at Besshiyama, a village at an altitude exceeding 1,000 meters, Sumitomo confirmed the existence of an excellent deposit and started mining in the following year. Sumitomo recruited workers from around Japan to labor in the mines and transport the ore, quickly establishing the necessary infrastructure for mining. According to the records, by 1695, just five years after the discovery of the deposit, there was already a bustling town of 2,700 people, mostly mineworkers, complete with shops and other businesses. Thus, amid this mountainous landscape, the Besshi Copper Mines were born.

The Besshi Copper Mines remained one of the leading sources of copper in Japan and the world for nearly 200 years, throughout the Edo period.

Rapid modernization

The south entrance of Adit No. 1 opened in 1886
Photo courtesy of Sumitomo Historical Archives

In the Meiji Era, in response to the government’s policy of promoting the industrial development of Japan, Sumitomo decided to modernize the Besshi Copper Mines. Sumitomo hired a foreign engineer, established a plan, and launched a decisive reform program in 1876. Whereas the mining had previously relied solely on manpower, Sumitomo introduced the use of gunpowder and dynamite to the mining process. As well as excavating an inclined shaft for discharging ore on the Toen Inclined Shaft, a hoist powered by a steam engine enabled efficient discharge of the ore. Whereas porters had previously transported the ore from deep underground to the foot of the mountain along a steep mountain path, a pathway suitable for ox-drawn wagons was constructed. And in 1893, a railway was laid. Within ten years or so, the Besshi Copper Mines achieved rapid modernization.

Coexistence with the region and into the sunset

The Hadeba Entrance of Adit No. 4 opened in 1915. Located 156 meters above sea level, it served as the main artery until the closure of the mines

In mining, it is customary to start at the upper layer where it is easy to reach the vein and then dig downward. The Besshi Copper Mines followed this pattern. The initial pithead was near the mountain peak, at an altitude of over 1,000 meters. When the vein was exhausted, a new pithead was established below the initial one so that digging could continue. From the Meiji era to the Taisho era, Adits No. 1, No. 3, and No. 4, which are the principal horizontal galleries extending toward the vein, were excavated on the northern slope of the Akaishi Mountain Range overlooking the Seto Inland Sea. Adjacent to the tunnel entrance and close the ore sorting yard, a mining town grew up. The mining settlements around Adits No. 3 and No. 4, located at a lower altitude, were in the outskirts of Niihama.

Niihama grew from strength to strength as the mining sector prompted companies to set up smelting, machine building, chemical production, electricity supply, and forestry operations. Centering on the Besshi Copper Mines, Niihama grew to be one of the leading cities along the coastline of the Seto Inland Sea.

By the mid-1960s, the shaft had reached about 1,000 meters below sea level, making mining more burdensome. Imports to Japan of ore from mines where labor costs were low took off and the Besshi Copper Mines started to lose their shine. Finally, in 1973, in the aftermath of the Nixon shock, the Besshi Copper Mines closed. With accumulated copper production of 650,000 tons during the entire period of operation from 1691 to 1973, the Besshi Copper Mines were the second biggest source of copper in Japan, following the Ashio Copper Mine.

To this day, mining facilities and the smelter are preserved in an area extending from the mountaintop to Niihama and on to Shisakajima Island in the Seto Inland Sea. The physical legacy of this industrial heritage is eloquent testimony to our forerunners’ painstaking efforts and their purposeful way of life. Although their work is finished, galleries and shafts stretching 700 kilometers attest to their heroic efforts.

Hadeba Hydroelectric Power Plant established in 1912. It continued to supply electricity to the Besshi Copper Mines until their closure.
Former Hoshigoe Station Building. Near the station building are remains of the ore sorting yard and company housing.

Significance of the Besshi Copper Mines
Copper bars from Besshi exported to the world

Japan used to be a major copper producer in the world

Photo courtesy of Sumitomo Historical Archives

Take a look at the many copper statues of the Buddha in Japan, most notably the Great Buddha in Nara created in the eighth century, and you can well imagine that Japan had been blessed with rich copper resources since ancient days. Volcanic activity caused by the sinking of tectonic plates into volcanic belts wrought a metamorphosis of the Earth’s crust, creating copious mineral deposits.

Although mining had flourished in ancient times, it lost momentum in the 15th century owing to sluggish technological development. However, during the Sengoku period at the end of the 15th century, feudal lords around Japan emphasized trading and industrial development, including mines, in order to stabilize livelihoods and strengthen military power. Moreover, with the advent of the Age of Exploration, Europeans started to visit Japan. The Portuguese, Spanish, Dutch, and British royal houses and their chartered companies profited by trading gold, silver, copper, and other minerals from Japan.

From the 15th to the 17th century, the development of gold and silver mines was energetically pursued in Japan. Indeed, at one point, mines in Japan accounted for one-third of the world’s silver production. This may be the background to Marco Polo’s reference to “Zipangu” as the “Land of Gold.”

Contribution to growth of the Japanese economy

By the beginning of the Tokugawa shogunate in 1600, silver production had lost momentum and copper production was on the rise. In the early 17th century, the development of copper mines was vigorously promoted. Many copper mines were opened including the Ashio Copper Mine (Tochigi Prefecture) as well as those in Hitachi (Ibaraki Prefecture), Nagato (Yamaguchi Prefecture), Suo (Yamaguchi Prefecture), and Buzen (Fukuoka Prefecture and Oita Prefecture), and copper was exported from Japan to the world.

Moreover, copper production sharply increased from around the 1660s in Japan. The discovery of the copper deposit at Besshi occurred in the middle of this “copper rush.”

Sumitomo began managing a mine in northeastern Honshu in the 1660s, opened the Yoshioka Copper Mine (Okayama Prefecture) in 1680 and, on the other side of the Seto Inland Sea, the Besshi Copper Mines in 1691, promoting development at a fast pace. Annual copper production of the Besshi Copper Mines had reached 1,500 tons within seven years from the opening, accounting for a quarter of Japan’s copper production. The contribution of the Besshi Copper Mines to the Japanese economy was undoubtedly significant.