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Archipelago

    Mizushima SeaJapan

    34°23′N 133°43′E

    Shiwaku Islands

    塩飽諸島

    Part of Bisan Islands

    The Shiwaku Islands (塩飽諸島, Shiwaku-shotō) or Shiwaku-jima (塩飽島) are an archipelago in the Seto Inland Sea, between the larger Japanese islands of Honshu and Shikoku.

    香川県丸亀市塩飽本島
    香川県丸亀市塩飽本島

    皓月旗 / CC BY-SA 4.0

    Chart

    52 landforms

    Overview

    The Shiwaku Islands (塩飽諸島, Shiwaku-shotō) or Shiwaku-jima (塩飽島) are an archipelago in the Seto Inland Sea, between the larger Japanese islands of Honshu and Shikoku. The group is part of Kagawa Prefecture and consists of 28 islands of various sizes. To the northwest, in Okayama Prefecture lie the Kasaoka Islands. The name derives from shioyaku (塩焼く) or shiowaku (潮湧く) both meaning boiling seawater to get salt. However, the name may also refer to rough water created by the confluence of tides that mix around the islands.

    From Wikipedia, CC BY-SA 4.0

    Census, cataloged

    • Major islands4
    • Minor islands11
    • Islets11
    • Rocks & skerries26

    Major islands

    4
    • Hiroshima

      Hiroshima

      Area
      11.8 km²
      High point
      312 m
    • Honjima

      Honjima

      Area
      6.7 km²
      High point
      204 m
    • Awashima

      Awashima

      Area
      3.6 km²
      High point
      222 m

      5 km northwest of the port of Takuma in the city of Mitoyo, Kagawa Prefecture. 72 km2 with a population of 216 (as of 2015). The island was the site of a maritime school that operated from 1897 to 1987, now preserved as a museum. The former post office is the site of the Missing Post Office.

    • Sanagi Island

      Sanagi Island

      Area
      1.8 km²
      High point
      248 m

    Minor islands

    11

    Islets

    11
    • Wasashima14 m · 0.06 km²
    • Bentenjima6 m · 0.02 km²
    • Shiwaku Islands4 m · 0.01 km²
    • Nabe Island5 m · 0.9 ha
    • Mitsugoshima1 m · 0.9 ha
    • Unnamed island0.4 ha
    • Hasetsu Iwa0.3 ha
    • Unnamed island0.2 ha
    • Unnamed island0.1 ha
    • Unnamed island0.1 ha
    • Unnamed island0.1 ha

    Rocks & skerries

    26
    • Unnamed island<0.1 ha
    • Unnamed island<0.1 ha
    • Shiwaku Islands<0.1 ha
    • Unnamed island<0.1 ha
    • Unnamed island<0.1 ha
    • Unnamed island<0.1 ha
    • Unnamed island<0.1 ha
    • Unnamed island<0.1 ha
    • Unnamed island<0.1 ha
    • Unnamed island<0.1 ha
    • Unnamed island<0.1 ha
    • Unnamed island<0.1 ha

    Also in the area

    1

    Inside the group's outline but not confirmed as members by any source.

    • Unnamed island<0.1 ha

    Figures

    Comparative heights

    Sea level100 m200 m300 m400 m312 mHiroshima248 mSanagi222 mAwashima204 mHonjima154 mShiwaku Islands107 mShishijima95 mUshijima95 mOteshima77 mHitsuishijima65 mYoshima47 mMukaijima47 mOyoshima45 mShiwaku Islands29 mIwakurojima
    High points by island, metres above sea level.

    Islands by area

    0.0000010.000010.00010.0010.010.1110100Hiroshima: 11.8 km²HiroshimaHonjima: 6.7 km²HonjimaAwashima: 3.6 km²AwashimaSanagi: 1.8 km²SanagiYoshima: 1.1 km²YoshimaHitsuishijima: 0.91 km²HitsuishijimaUshijima: 0.82 km²UshijimaShishijima: 0.62 km²ShishijimaOteshima: 0.55 km²OteshimaMukaijima: 0.32 km²MukaijimaShiwaku Islands: 0.28 km²Shiwaku IslandsOyoshima: 0.27 km²OyoshimaIwakurojima: 0.16 km²IwakurojimaShiwaku Islands: 0.13 km²Shiwaku IslandsWasashima: 0.06 km²WasashimaBentenjima: 0.02 km²BentenjimaShiwaku Islands: 0.01 km²Shiwaku IslandsNabe: 0.9 haNabeMitsugoshima: 0.9 haMitsugoshimaUnnamed island: 0.4 haUnnamed islandHasetsu Iwa: 0.3 haHasetsu IwaUnnamed island: 0.2 haUnnamed islandUnnamed island: 0.1 haUnnamed islandUnnamed island: 0.1 haUnnamed islandUnnamed island: 0.1 haUnnamed islandUnnamed island: <0.1 haUnnamed islandUnnamed island: <0.1 haUnnamed islandShiwaku Islands: <0.1 haShiwaku IslandsUnnamed island: <0.1 haUnnamed islandUnnamed island: <0.1 haUnnamed islandUnnamed island: <0.1 haUnnamed islandUnnamed island: <0.1 haUnnamed islandUnnamed island: <0.1 haUnnamed islandUnnamed island: <0.1 haUnnamed islandUnnamed island: <0.1 haUnnamed islandUnnamed island: <0.1 haUnnamed islandUnnamed island: <0.1 haUnnamed islandUnnamed island: <0.1 haUnnamed islandUnnamed island: <0.1 haUnnamed islandUnnamed island: <0.1 haUnnamed island
    km², log scale. 1 without a known area.
    Hiroshima11.8 km²
    Honjima6.7 km²
    Awashima3.6 km²
    Sanagi Island1.8 km²
    Yoshima1.1 km²
    Hitsuishijima0.91 km²
    Ushijima0.82 km²
    Shishijima0.62 km²
    Oteshima0.55 km²
    Mukaijima0.32 km²
    Shiwaku Islands0.28 km²
    Oyoshima0.27 km²
    Iwakurojima0.16 km²
    Shiwaku Islands0.13 km²
    Wasashima0.06 km²
    Bentenjima0.02 km²
    Shiwaku Islands0.01 km²
    Nabe Island0.9 ha
    Mitsugoshima0.9 ha
    Unnamed island0.4 ha
    Hasetsu Iwa0.3 ha
    Unnamed island0.2 ha
    Unnamed island0.1 ha
    Unnamed island0.1 ha
    Unnamed island0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Shiwaku Islands<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha
    Unnamed island<0.1 ha

    Sources

    Facts

    • Geometry, areas and high points: OpenStreetMap contributors (ODbL), Copernicus GLO-30, via Talus.
    • Wikidata
    • Talus
    • Wikipedia

    Photographs