What is nihonkai?

Nihonkai, also known as the Sea of Japan, is a marginal sea located between Japan and the Asian continent. It covers an area of approximately 978,000 square kilometers and has a maximum depth of 3,742 meters. The sea is surrounded by the Japanese islands on the east, the Russian Far East and Korea on the west and north, and the Hokkaido and Honshu islands on the south. The sea is rich in marine life and supports important fisheries, including squid, crab, and salmon. It is also a major shipping route connecting ports in Japan, Russia, China, and South Korea. The sea is prone to earthquakes and tsunamis due to its location on the Pacific Ring of Fire.