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Tokyo Bay

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Tokyo Bay is a major body of water in Japan. It is located in the southern Kantō region. The bay sits on the southern coast of the island of Honshu. It spans the coasts of Tokyo, Kanagawa Prefecture, and Chiba Prefecture. The bay is connected to the Pacific Ocean by the Uraga Channel.

Tokyobay area
Tokyobay area

This region is the largest industrialized area in Japan. It is also the most populous region in the country. The bay juts into the Kantō Plain. It is surrounded by two peninsulas. The Bōsō Peninsula is to the east in Chiba Prefecture. The Miura Peninsula is to the west in Kanagawa Prefecture.

There are different ways to define the boundaries of the bay. In a narrow sense, the bay is the area north of a straight line. This line runs from Cape Kannon on the Miura Peninsula to Cape Futtsu on the Bōsō Peninsula. This narrow area covered about 1,180 square kilometers in 2012. In a broader sense, the bay includes the Uraga Channel. This larger area runs from Cape Tsurugisaki to Cape Sunosaki. This broader definition covers about 2,580 square kilometers. The combined area of the bay and the channel is 2,780 square kilometers.

Tokyobay area
Tokyobay area

The underwater shape of the bay varies by location. A shoal, or shallow area, exists between Cape Futtsu and Cape Honmaku in Yokohama. This area is called Nakanose. It has a depth of only 10 meters. North of Nakanose, the bay has a depth of 30 meters. The underwater topography there is uncomplicated. Areas south of Nakanose are significantly deeper as they move toward the Pacific Ocean. Many rivers empty into the bay. The Tama and Sumida rivers flow into the bay at Tokyo. The Edo River flows between Tokyo and Chiba. In Chiba, the Obitsu and Yōrō rivers also empty into the water. These rivers provide water for residential and industrial areas.

The name of the bay has changed throughout history. In ancient times, the Japanese knew it as Edo Bay. During the Azuchi–Momoyama period, it was known as Edo Bay. This was named after the city of Edo. The bay took its current name in modern times. In 1868, the Imperial court moved to Edo. They renamed the city Tokyo. This change gave the bay its present name.

Historically, the bay was a center for the fishing industry. This included shellfish and other aquaculture. These industries decreased as the region became more industrial in the 20th century. They almost completely stopped after the construction of industrial zones.

Land reclamation has changed the shape of the shoreline. This is the process of creating new land from the sea. Reclamation has happened since the Meiji period. People use sand from the bay floor for these projects. In 2012, reclaimed land made up about 15% of the bay area. Many artificial islands were built for military forts. After World War II, these were used for homes or fun. Odaiba was one of six artificial islands built in 1853. It was meant to protect the Tokugawa shogunate. Now, Odaiba is used for business and recreation.

Night in the Greater Tokyo Area ISS054
Night in the Greater Tokyo Area ISS054

Other islands in the bay have unique histories. Sarushima is the only natural island in the bay. It was once a fortified location for coastal artillery. It is now an uninhabited marine park. Yumenoshima was once planned as a massive airfield. Instead, it was used as a landfill for garbage from 1957 to 1967. Today, it is Yumenoshima Park. Hakkei Island was also once a landfill. It is now home to the Yokohama Hakkeijima Sea Paradise. The bay also hosts the Keihin and Keiyō industrial zones. These zones make the bay the largest industrial area in Japan. They have caused significant air and water pollution.

Tokyo Bay is home to many important ports. These include the Ports of Yokohama, Chiba, Tokyo, Kawasaki, Yokosuka, and Kisarazu. They are among the busiest ports in the Asia-Pacific Region. The bay has also seen major world events. In 1853, Commodore Matthew Perry sailed his "Black Ships" into the bay. This led to a peace and trade treaty with the United States. Later, the bay hosted the end of World War II. On September 2, 1945, the Japanese Instrument of Surrender was signed. It was signed on the USS Missouri. The ship was anchored in the bay.

Missouri-flyover
Missouri-flyover
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File:Night_in_the_Greater_Tokyo_Area_ISS054.jpg
Night_in_the_Greater_Tokyo_Area_ISS054.jpg
File:Tokyobay area.png
Tokyobay area.png
File:Tsukada_Island_in_the_Musashi_province.jpg
Tsukada_Island_in_the_Musashi_province.jpg
File:Missouri-flyover.jpg
Missouri-flyover.jpg
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