yeah, landlocked by land. Land that belongs to nations. More than one. Thus international. And treaties that extend the invitation to other nations to use the waters.

"Three NATO countries—Romania, Bulgaria, and Turkey—also have a coast on the Black Sea. Get all our news and commentary in your inbox at 6 a.m. ET. Although the sea is international waters, only warships from the countries along its coastline can stay more than three weeks under the Montreux Convention of 1936."

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