was the name of a group of

coastal fortification 300px, Castillo San Felipe de Barajas in Cartagena de Indias, Colombia, an example of an Early Modern coastal defense Coastal defence (or defense) and coastal fortification are measures taken to provide protection against military attack at or ...

s built to guard the Hōyo Strait at the entrance to Bungo Channel between the Japanese islands of

Kyushu is the third-largest island of Japan's five main islands and the most southerly of the four largest islands ( i.e. excluding Okinawa). In the past, it has been known as , and . The historical regional name referred to Kyushu and its surroun ...

and Shikoku and this the western entrance to the

Seto Inland Sea The , sometimes shortened to the Inland Sea, is the body of water separating Honshū, Shikoku, and Kyūshū, three of the four main islands of Japan. It serves as a waterway connecting the Pacific Ocean to the Sea of Japan. It connects to Osaka ...

. These gun batteries and fortifications ceased to be used after the end of World War II.

History

After the Meiji restoration, the primary threats to the new Empire of Japan were perceived to be

Qing China The Qing dynasty ( ), officially the Great Qing,, was a Manchu people, Manchu-led Dynasties in Chinese history, imperial dynasty of China and the last orthodox dynasty in Chinese history. It emerged from the Later Jin (1616–1636), La ...

's Beiyang fleet, followed by the Russian Empire's Pacific Fleet. The Meiji government ordered the construction of a set of coastal fortifications to protect the strategic waterway and approaches to major coastal cities. Initially, the Hiroshima Port Fortress was constructed to protect the city of Hiroshima, which was the location of the

Imperial General Headquarters The was part of the Supreme War Council and was established in 1893 to coordinate efforts between the Imperial Japanese Army and Imperial Japanese Navy during wartime. In terms of function, it was approximately equivalent to the United States ...

in the First Sino-Japanese War and the Geiyō Fortress was constructed to control the Kurushima Strait, a narrows in the Seto Inland Sea between Hiroshima and Shikoku, which blocked the western approaches to

Kobe Kobe ( , ; officially , ) is the capital city of Hyōgo Prefecture Japan. With a population around 1.5 million, Kobe is Japan's seventh-largest city and the third-largest port city after Tokyo and Yokohama. It is located in Kansai region, whic ...

and Osaka. From 1920, construction began on coastal fortifications to control the much wider Bungo Channel. Geiyō Fortress was abolished in 1924 and Hiroshima Bay Fortress in 1926. A second groups of batteries were completed between 1930 and 1934. The fortifications were in five groups: the island of Takashima and Cape Sekizaki (both in the city of Ōita, Cape Tsuru (in Saiki, Ōita), Saganoseki Saganoseki, Ōita, and Cape Sada (

Ikata is a small peninsula town located in Nishiuwa District, Ehime Prefecture, Japan. , the town had an estimated population of 8,497 in 15638 households and a population density of 90 persons per km². The total area of the town is Following a rec ...

, Nishiuwa District, Ehime). The largest guns installed were 28-cm howitzers of the same type which were under during the Russo-Japanese War at the Siege of Port Arthur to get effect against the Russian Pacific Fleet. From the 1920s and 1930s, many surplus guns of the Imperial Japanese Navy, which had been made available due to the reduction of capital warships per the

London Naval Treaty The London Naval Treaty, officially the Treaty for the Limitation and Reduction of Naval Armament, was an agreement between the United Kingdom, Japan, France, Italy, and the United States that was signed on 22 April 1930. Seeking to address is ...

and the Washington Naval Treaty, were reused in these coastal artillery installations. With the approach of World War II, efforts were made to modernize and strength these coastal batteries. In particular, at the Taga Battery in Saiki, Oita, the EOC 12-inch 45-calibre naval guns formerly used as the main battery of the scrapped cruiser were installed. During a training exercise in January 1942, one of these guns exploded due to a turret breach, killing 16 men and injuring 18 others. All fortifications were dismantled at the end of World War II.

Gun emplacements

Takashima Island

* Takashima No.1 Battery (2x 12cm rapid fire guns) * Takashima No.2 Battery (4x 30cm howitzers) * Takashima No.3 Battery (4x 12-cm rapid fire cannons)

Cape Sekizaki

* Sekizaki Battery (15cm rapid fire cannon)

Cape Sada

* Sadamisaki No.1 Battery (4x 15cm howitzer, removed 1944) * Sadamisaki No.2 Battery (4x cannon, removed 1944) * Sadamisaki No.3 Battery (2x

Type 38 12 cm howitzer The Type 38 12 cm howitzer (1905) is an obsolete Japanese field piece used by the Imperial Japanese Army during World War I, Second Sino-Japanese War, and World War II. The Type 38 designation was given to this gun as it was accepted in the ...

, installed 1945) * Sadamisaki No.4 Battery (2x

, installed 1945)

Cape Tsurumisaki

* Taga 1st Battery (26 x 30cm cannon, damaged January 1942) * Tsurumisaki No.1 Battery (4x 15cm cannon) * Tsurumisaki No.2 Battery (4x 12cm howitzer)

Saganoseki

* Shiroki Main Magazine

External links

*{{Commons category-inline, Sadamisaki Artillery battery History of Ehime Prefecture History of Ōita Prefecture Coastal fortifications Imperial Japanese Army