Some 500 people gathered at the event in Shimane prefecture in western Japan, including a high-ranking Japanese government official as well as local and national politicians, organisers said.
Tokyo refers to the islands in the Sea of Japan (East Sea) as Takeshima, while they are known as Dokdo in South Korea.
Yoshitami Kameoka, a parliamentary secretary in Tokyo's Cabinet Office, attended the event representing the government of Prime Minister Shinzo Abe, the organisers said.
Relations between the two countries have regularly been strained by the territorial dispute and other issues arising from Japan's 1910-45 colonial rule over the Korean peninsula.
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