Canals, lakes, rivers, water courses, inlets, and bays that are nearest to the shores of a nation and subject to its complete sovereignty.
Inland waters, also known as internal waters, are subject to the total sovereignty of the country as much as if they were an actual part of its land territory. A coastal nation has the right to exclude foreign vessels, subject to the right of entry in times of distress.
Whether or not particular waters are to be regarded as inland waters has traditionally been dependent upon historical and geographical factors. Certain types of shoreline configurations have been regarded as confining bodies of water, such as bays. In addition, there has been a recognition that other areas of water that are closely connected to the shore may be regarded as inland waters based upon the manner in which they have been treated by the coastal nation, although they do not meet any exact geographical test. Historic title to inland waters can be claimed only in situations when the coastal nation has asserted and maintained dominion and control over those waters.
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