How Many Miles From the Shore Are International Waters?

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Maritime boundaries can generally be divided between territorial waters and international waters, which begin 12 nautical miles from a sovereign coastline, according to Geoscience Australia. The U.S. Coast Guard explains that international law generally prohibits any nation from asserting jurisdiction over foreign vessels on international waters.

Most sovereign states also have a contiguous zone limited to 24 nautical miles and an exclusive economic zone limited to 200 nautical miles. According to Geoscience Australia, the contiguous zone is a belt of water that includes the territorial sea where sovereign powers can exercise control necessary to prevent and punish infringement of its customs, fiscal, immigration or sanitary laws and regulations within its territory. The exclusive economic zone includes the contiguous zone and is limited to 200 nautical miles from the sovereign baseline. Geoscience Australia explains that a sovereign power has rights to this zone for the purpose of exploring, conserving and managing all natural resources of the waters.