is an island located in the eastern part of the
Sea of Japan
The Sea of Japan is the marginal sea between the Japanese archipelago, Sakhalin, the Korean Peninsula, and the mainland of the Russian Far East. The Japanese archipelago separates the sea from the Pacific Ocean. Like the Mediterranean Sea, it ...
, under the jurisdiction of
Sado City,
Niigata Prefecture
is a Prefectures of Japan, prefecture in the Chūbu region of Honshu of Japan. Niigata Prefecture has a population of 2,131,009 (1 July 2023) and is the List of Japanese prefectures by area, fifth-largest prefecture of Japan by geographic area ...
,
Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
, with a coastline of . In October 2017, Sado Island had a population of 55,212 people. Sado Island covers an area of , and is the second largest island after
Okinawa Island
, officially , is the largest of the Okinawa Islands and the Ryukyu Islands, Ryukyu (''Nansei'') Islands of Japan in the Kyushu region. It is the smallest and least populated of the five Japanese archipelago, main islands of Japan. The island is ...
outside of the four main islands of Japan, excluding the disputed
Southern Kurils.
The shortest distance between Sado Island and
Honshu
, historically known as , is the largest of the four main islands of Japan. It lies between the Pacific Ocean (east) and the Sea of Japan (west). It is the list of islands by area, seventh-largest island in the world, and the list of islands by ...
is .
[ ] The highest peak on Sado Island is
Mount Kinpoku, with an elevation of .
Geography
The shape of Sado Island resembles the kanji character for ‘work’ (工) in Japanese or the letter ‘S’. The topography of the island can be roughly divided into three parts, the Ōsado range in the north, the Kosado range in the south, and the Kakakura plain with flat terrain in between. The Ōsado range area is higher in altitude, and the highest peak of Sado Island, Mount Kinpoku ( above sea level), is also located in this area. The coastline on the north side of Mount Sado is steep, and is a famous tourist spot, among which the Senkaku Bay is the most famous. The Kosado range has a relatively flatter terrain with
Satsuma orange and
tea trees growing there. Its highest peak is Mount Ōjiyama, with an elevation of . The Nakakura Plain is a large plain in Japan's outlying islands and is also the agricultural area of Sado Island. On the west side of the Kuninaka Plain is
Mano Bay, and on the east side is
Ryōtsu Bay. The Kokufugawa River (also reads Konogawa River) flows through the Kuninaka Plain, with a total length of , and flows into Mano Bay. Its watershed area accounts for 20% of Sado Island.
Lake Kamo, the largest lake in Niigata Prefecture, is located at the eastern end of the Kuninaka Plain. Lake Kamo was originally a
freshwater lake, and later turned into a
lagoon
A lagoon is a shallow body of water separated from a larger body of water by a narrow landform, such as reefs, barrier islands, barrier peninsulas, or isthmuses. Lagoons are commonly divided into ''coastal lagoons'' (or ''barrier lagoons'') an ...
after an opening built to the Sea of Japan.
Oyster
Oyster is the common name for a number of different families of salt-water bivalve molluscs that live in marine or brackish habitats. In some species, the valves are highly calcified, and many are somewhat irregular in shape. Many, but no ...
breeding flourishes in the lake. Part of Sado Island belongs to the
Sado-Yahiko-Yoneyama Quasi-National Park.
Gallery
Weather and climate
Affected by the warm
Black Current that passes through the Sado waters, the winter in Sado Island is warmer than that in Niigata Prefecture and with less snow. In summer, due to the influence of ocean, the temperature difference between day and night is smaller than that of Niigata Prefecture, and is cooler than that of Niigata Prefecture. However, the Aikawa area on the northwestern side of the Ōsado range are affected by the monsoon blowing from the northwest and the temperature is higher. Precipitation on Sado Island is mainly concentrated in the end of the
East Asian rainy season
The East Asian rainy season (), also called the plum rain, is caused by precipitation along a persistent stationary front known as the Meiyu front for nearly two months during the late spring and early summer in East Asia between China, Taiwan ...
and early winter, and there is less precipitation than in Niigata Prefecture. When the low air pressure and
typhoon
A typhoon is a tropical cyclone that develops between 180° and 100°E in the Northern Hemisphere and which produces sustained hurricane-force winds of at least . This region is referred to as the Northwestern Pacific Basin, accounting for a ...
s pass through the Sea of Japan, Sado Island often suffers from
Foehn wind, raising the temperature sharply. Located at the junction of the warm and cold current, Sado City enjoys diverse plants and rich aquatic resources.
Flora and fauna
Because it is located at the junction of warm and cold
currents
Currents, Current or The Current may refer to:
Science and technology
* Current (fluid), the flow of a liquid or a gas
** Air current, a flow of air
** Ocean current, a current in the ocean
*** Rip current, a kind of water current
** Current (hy ...
, it is extremely rich in vegetation, making it an extremely rare vegetation area on the island where plants unique to both Hokkaido and Okinawa coexist. It is also blessed with a variety of marine products, such as dolphinfish, bonito, and bigfin squid that appear in warm currents, and yellowtail that appears in cold currents.
Due to the hundreds of thousands of years that have passed since it was isolated from Honshu island, endemic species such as the Sado hare, Sado mole, and Sado shrew can be seen. Although they are now extinct, there was a population of wild boars that was genetically separated from the population of Honshu for hundreds of thousands of years. The Japanese weasel is said to have been re-introduced after becoming locally extinct.
History
Sado Island was originally connected to Honshu, but it separated from Honshu around 16 million years ago due to changes in the topography due to tectonic deformation and volcanic activity, and around 2 million years ago, the ground began to collapse due to compressive kinetic energy in the ocean floor. It is thought that the area rose to its current shape, with the Osado Mountains and Kosado Hills sandwiching the Kuninaka Plain. Uplift continues to this day due to tectonic movements such as earthquakes.

With a long history, Sado Island has been inhabited by humans for 10,000 years. Thousands of ruins discovered in the Kanai area included stoneware and hunting equipment from the late
Yayoi period
The Yayoi period (弥生時代, ''Yayoi jidai'') (c. 300 BC – 300 AD) is one of the major historical periods of the Japanese archipelago. It is generally defined as the era between the beginning of food production in Japan and the emergence o ...
. There are also records of Sado in the ''
Kojiki
The , also sometimes read as or , is an early Japanese chronicle of myths, legends, hymns, genealogies, oral traditions, and semi-historical accounts down to 641 concerning the origin of the Japanese archipelago, the , and the Japanese imperia ...
'' and ''
Nihongi''. After the
Taika Reform
The were a set of doctrines established by Emperor Kōtoku (孝徳天皇 ''Kōtoku tennō'') in the year 645. They were written shortly after the death of Prince Shōtoku and the defeat of the Soga clan (蘇我氏 ''Soga no uji''), uniting Jap ...
, the central government established the
Sado Province on the island, and the local population began to emigrate to Sado Island. At the same time, Sado Island has also become the place where losers of political conflicts or
dissident
A dissident is a person who actively challenges an established political or religious system, doctrine, belief, policy, or institution. In a religious context, the word has been used since the 18th century, and in the political sense since the 2 ...
s were
exiled.
Emperor Juntoku
(22 October 1197 – 7 October 1242) was the 84th emperor of Japan, according to the traditional order of succession. His reign spanned the years from 1210 through 1221, a part of Japan's Kamakura Period.
Genealogy
Before his ascension to the C ...
,
Nichiren
was a Japanese Buddhist priest and philosopher of the Kamakura period. His teachings form the basis of Nichiren Buddhism, a unique branch of Japanese Mahayana Buddhism based on the '' Lotus Sutra''.
Nichiren declared that the '' Lotus Sutra ...
and other people had been exiled to Sado. After the
Kamakura period
The is a period of History of Japan, Japanese history that marks the governance by the Kamakura shogunate, officially established in 1192 in Kamakura, Kanagawa, Kamakura by the first ''shōgun'' Minamoto no Yoritomo after the conclusion of the G ...
, the
Honma clan was appointed as the Shugodai. After 1589 ( Tenshō 17),
Uesugi Kagekatsu invaded Sado Island, after which Sado Island was dominated by the
Uesugi clan
The is a Japanese samurai clan which was at its peak one of the most powerful during the Muromachi period, Muromachi and Sengoku periods (14th to 17th centuries).Georges Appert, Appert, Georges. (1888) ''Ancien Japon,'' p. 79./ref> At its heigh ...
.
In 1601, miners discovered veins of gold and silver in the Aikawa Tsuruko Ginzan, which became the
Sado Mine. In 1603 (Keichō 8),
Tokugawa Ieyasu
Tokugawa Ieyasu (born Matsudaira Takechiyo; 31 January 1543 – 1 June 1616) was the founder and first ''shōgun'' of the Tokugawa shogunate of Japan, which ruled from 1603 until the Meiji Restoration in 1868. He was the third of the three "Gr ...
classified Sado Island as a
territory of the Bakufu immediately after his victory at the
Battle of Sekigahara
The Battle of Sekigahara (Shinjitai: ; Kyūjitai: , Hepburn romanization: ''Sekigahara no Tatakai'') was an important battle in Japan which occurred on October 21, 1600 (Keichō 5, 15th day of the 9th month) in what is now Gifu Prefecture, ...
. Sado Mine developed into the largest goldmine in Japan. Its output reached 41 tons by the
Bakumatsu
were the final years of the Edo period when the Tokugawa shogunate Meiji Restoration, ended. Between 1853 and 1867, under foreign diplomatic and military pressure, Japan ended its isolationist foreign policy known as and changed from a Feudali ...
period in the mid-19th century, and it played an important role in the financing of the
Shogunate
, officially , was the title of the military rulers of Japan during most of the period spanning from 1185 to 1868. Nominally appointed by the Emperor, shoguns were usually the de facto rulers of the country, except during parts of the Kamak ...
. After the middle of the
Edo period
The , also known as the , is the period between 1600 or 1603 and 1868 in the history of Japan, when the country was under the rule of the Tokugawa shogunate and some 300 regional ''daimyo'', or feudal lords. Emerging from the chaos of the Sengok ...
, the quantity began to decrease, but output rose to the highest level ever, at 400 kg a year, thanks to the introduction of advanced excavation technology during the
Meiji era
The was an Japanese era name, era of History of Japan, Japanese history that extended from October 23, 1868, to July 30, 1912. The Meiji era was the first half of the Empire of Japan, when the Japanese people moved from being an isolated feu ...
in the late 19th century. Sado Gold Mine closed in 1989. In nearly 400 years of mining history, it produced 78 tons of gold and 2,300 tons of silver.
After the
abolition of the ''han'' system, the
Japanese government
The Government of Japan is the central government of Japan. It consists of legislative, executive and judiciary branches and functions under the framework established by the Constitution of Japan. Japan is a unitary state, containing forty- ...
established Sado Prefecture on Sado Island, but later renamed it
Aikawa Prefecture. In 1876, Aikawa Prefecture was incorporated into Niigata Prefecture. In 2004, ten cities, towns and villages on Sado Island were merged to form
Sado City.
Forced labor
Sado Island was the site of forced labor during
World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...
, when around 1,500 Koreans were conscripted and forced to work in the mines on the island. The Japanese government, some Japanese scholars, and a minority of international scholars oppose this claim. Koreans are even mentioned in an exhibit in one of the mines, but there is no implication that they were forced to work there.
In 2022, this became the subject of a diplomatic conflict between South Korea and Japan. Japan had previously added Hashima Island, another island where forced labor occurred (which Japan denies), to the
UNESCO World Heritage Site
World Heritage Sites are landmarks and areas with legal protection under an treaty, international treaty administered by UNESCO for having cultural, historical, or scientific significance. The sites are judged to contain "cultural and natural ...
list.
However, the nomination was only approved because South Korea and Japan had reached a deal where Japan would acknowledge forced labor in its exhibits. Japan, under the guidance of Japanese politician and Prime Minister
Fumio Kishida, went back on its word and created a museum denying that forced labor occurred on Hashima. All other 21 nations of the UNESCO committee agreed that Japan had failed to reach its side of the agreement, but Japan ignored requests to correct the museum. It subsequently filed to have Sado Island added to the list as well, which sparked international and domestic criticism.
This request was initially denied due to concerns over how the island's history would be presented.
Japan refiled the request on 28 January 2023, with the goal of being added to the list by 2024.
Various sources expressed skepticism on whether the bid would be successful.
However, on 27 July 2024, the UNESCO committee unanimously decided to register the Sado Island Gold Mines as a cultural heritage site.
The bid gained the support of South Korea following bilateral negotiations between the two countries. The Japanese government established an exhibit about the harsh working conditions, and promised to hold an annual memorial. Additionally, a representative for the Japanese government told the committee that Japan would make efforts to "comprehensively address the whole history of the Sado Island Gold Mines" in consultation with South Korea.
The listing has been described as an improvement in
Japan-South Korea relations,
although it has been met with criticism in South Korea.
South Korean President
Yoon Suk Yeol's friendlier position to Japan has been analyzed in the context of the approval.
Population
In 1960, Sado Island had a population of 113,296. Due to the inconvenience of living on the outlying islands and lack of jobs, Sado Island has experienced a long-term population decline. In October 2017, the population of Sado Island was 55,212. The
total fertility rate
The total fertility rate (TFR) of a population is the average number of children that are born to a woman over her lifetime, if they were to experience the exact current age-specific fertility rates (ASFRs) through their lifetime, and they were t ...
of Sado Island is about 1.9, which is much higher than the average of Japan and Niigata Prefecture. However, the continuous outflow of population results in the persistent decrease of population.
Culture

Since Sado Island is an important trading base on the
Nishimawari naval route from the coast of the Japan Sea to
Osaka
is a Cities designated by government ordinance of Japan, designated city in the Kansai region of Honshu in Japan. It is the capital of and most populous city in Osaka Prefecture, and the List of cities in Japan, third-most populous city in J ...
, the culture is strongly influenced by West Japanese culture like Kinki and Hokuriku. Intellectuals and politicians exiled from
Kyoto
Kyoto ( or ; Japanese language, Japanese: , ''Kyōto'' ), officially , is the capital city of Kyoto Prefecture in the Kansai region of Japan's largest and most populous island of Honshu. , the city had a population of 1.46 million, making it t ...
to Sado brought the traditional performance culture of Kyoto, which caused the traditional art of Sado Island to began to thrive. The
Noh Master
Zeami Motokiyo
, also called , was a Japanese aesthetician, actor, and playwright.
His father, Kan'ami Kiyotsugu, introduced him to Noh theater performance at a young age, and found that he was a skilled actor. Kan'ami was also skilled in acting and formed a ...
was exiled to Sado, resulting in the particular development of Noh culture in Sado. In the
Edo period
The , also known as the , is the period between 1600 or 1603 and 1868 in the history of Japan, when the country was under the rule of the Tokugawa shogunate and some 300 regional ''daimyo'', or feudal lords. Emerging from the chaos of the Sengok ...
, there were more than 200
Noh stages. Sado still has more than 30 Noh stages - ranking first in Japan in the number of Noh stages per capita. There are also local performing arts such as ‘Ghost Taiko’ on Sado Island.
Sado is also home to the
Kodō taiko
are a broad range of Traditional Japanese musical instruments, Japanese percussion instruments. In Japanese language, Japanese, the term refers to any kind of drum, but outside Japan, it is used specifically to refer to any of the various J ...
drumming troupe.
Kodō are credited with popularizing modern taiko drumming both in Japan and worldwide. Kodō Village is based in the
Ogi subdivision.
The round coracle-like
Tarai-bune boats were once common in different parts of Japan, but are now only found on Sado.
Transportation
See also
*
Sado, Niigata (municipality)
References
Notes
External links
Sado Tourism Association
Sado Geopark
Sado Steam Ship
{{Authority control
Islands of the Sea of Japan
Islands of Niigata Prefecture
Sado, Niigata
Forced labour during World War II
Prison islands
Forced labor in Japan