Territorial waters or a
territorial sea as defined by the 1982
United Nations Convention on the Law of the Sea, is a belt of
coastal waters extending at most from the
baseline (usually the mean low-water mark) of a coastal state. The territorial sea is regarded as the sovereign territory of the state, although foreign ships (both military and civilian) are allowed
innocent passage through it; this sovereignty also extends to the airspace over and seabed below. Adjustment of these boundaries is called, in international law,
maritime delimitation.