One of the sea forts that sunk to the bottom of Tokyo Bay.
No. 3 Sea Fort
A “kaiho,” or sea fort, refers to an artificial island constructed to serve as a gun battery. The guns from the 1870s to late 1920s had a limited firing range from land. In order to protect the waters that were out of range, three sea forts were constructed in Tokyo Bay. While the No. 3 Sea Fort was later demolished, some of the structures were preserved and placed on display at Heisei-cho and Natsushima-cho.
Information Basic information
3-23 Heisei-cho, Yokosuka (Within Umikaze Park) |
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(Oppama) 30-minute walk from Oppama Station or 5-minute walk from OPPAMASHAKO-MAE bus stop. |
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Natsushima: 10:00~16:00 |
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Natsushima: Open to public 1st Sunday of the month |
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046-822-8484 Lifelong Learning Div., Yokosuka City |
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