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Seto Inland Sea

geography Maturity 11-13 Next article →

The Seto Inland Sea is a beautiful body of water in Japan.

Chugoku-Region-Shikoku-Japan-ISS-Space
Chugoku-Region-Shikoku-Japan-ISS-Space

It sits between three of the country's main islands: Honshu, Shikoku, and Kyushu. This sea is not a closed lake. Instead, it is a marginal sea. This means it is part of the Pacific Ocean but is mostly tucked behind islands. The water connects the Pacific Ocean to the Sea of Japan.

Map of Honshu-Shikoku Bridge Project
Map of Honshu-Shikoku Bridge Project

It also links to Osaka Bay. This helps ships reach busy industrial centers like Osaka and Kobe. The area around the sea is called the Setouchi region. It has a mild climate with steady temperatures and low rainfall.

There is so much to see in these waters.

Setouchi
Setouchi

Almost 3,000 islands are scattered throughout the sea. Awaji-shima is the largest island, and Shōdo-shima is the second largest. Many of the smaller islands have no people living on them at all. More than 500 different marine species live here. You might find ayu fish, horseshoe crabs, or finless porpoises. Even great white sharks are known to swim in these waters. In the past, whales used to come here to eat or breed. However, they are rarely seen now because of pollution and whaling.

The history of this sea is very long and busy.

ItsukushimaTorii7492
ItsukushimaTorii7492

During the last ice age, the sea level was much lower. When the ice age ended, water filled a basin between two mountain ranges. This created the sea we see today. For a long time, the sea was the main path for travel. It connected Japan to other places like Korea and China. In the old days, powerful sea groups called suigun controlled many coastal areas. These groups were sometimes called pirates. They were very strong and often ruled themselves.

In the Edo period, the sea was one of the busiest places in Japan.

Wake behind a ferry
Wake behind a ferry

Many ships used the sea to travel around the islands. Big ports like Osaka and Sakai were very important. Because of this trade, Osaka became a huge economic center. Later, as cities grew, they became very industrial. Many cities along the coast now make things like steel and cars. Some places even build huge ships. Imabari is home to Japan's largest shipbuilding company. Fishing and tourism also bring a lot of money to the people living nearby.

Today, we use new ways to cross the water.

Akashi Bridge
Akashi Bridge

In the late 20th century, a big project built bridges to connect the islands. This is called the Honshū–Shikoku Bridge Project. The Akashi Kaikyō Bridge is one of the longest suspension bridges in the world. The Great Seto Bridge is also special because it carries both cars and trains. There is even a highway with ten bridges that connects many small islands.

Mount Ishizuchi
Mount Ishizuchi

These paths make travel much faster than the old ferry boats. The sea remains a vital path for ships carrying goods all over the world.

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🖼️ Images & Media (7)
File:Chugoku-Region-Shikoku-Japan-ISS-Space.png
Chugoku-Region-Shikoku-Japan-ISS-Space.png
File:Setouchi.jpg
Setouchi.jpg
File:ItsukushimaTorii7492.jpg
ItsukushimaTorii7492.jpg
File:Map_of_Honshu-Shikoku_Bridge_Project.svg
Map_of_Honshu-Shikoku_Bridge_Project.svg
File:Wake behind a ferry.jpg
Wake behind a ferry.jpg
File:Akashi_Bridge.JPG
Akashi_Bridge.JPG
File:Mount_Ishizuchi.jpg
Mount_Ishizuchi.jpg
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