English Wikipedia has a category on:
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Commons:Category
Commons:Category
Wikimedia Commons has more media related to:
Newest and oldest pages 
Newest pages ordered by last category link update:
  1. 瀨戶內海
  2. 哈德逊湾
  3. 阿拉伯海
  4. 亚速海
  5. 巴倫支海
  6. 勃海
  7. 墨西哥湾
  8. 哈得孙湾
  9. 哈德森湾
  10. 波罗的海
Oldest pages ordered by last edit:
  1. 愛爾蘭海
  2. 爱尔兰海
  3. 亞得里亞海
  4. 英吉利海峽
  5. 英吉利海峡
  6. 紅海
  7. 北海
  8. 地中海

Chinese names of seas.

NOTE: This is a name category. It should contain names of specific seas, not merely terms related to seas, and should also not contain general terms for types of seas.