Territorial waters

Territorial waters, or a territorial sea, is a belt of coastal waters extending twelve nautical miles from the shore of a littoral state that is regarded as the sovereign territory of the state, except that foreign ships (both military and civilian) are allowed innocent passage through it.
A sovereign state has complete jurisdiction over internal waters, where not even innocent passage is allowed. Territorial waters extend out 12 nautical miles (22 km) from the mean low water mark adjacent to land, or from internal waters, per the 1994 United Nations Convention on the Law of the Sea. The mean low water mark may be an unlimited distance from permanently exposed land provided that some portion of elevations exposed at low tide but covered at high tide (like mud flats) is within 12 nautical miles of permanently exposed land. Completely enclosed seas, lakes, and rivers are considered internal waters, as are waters landward of lines connecting fringing islands along a coast or landward of lines across the mouths of rivers that flow into the sea. Bays are defined as indentations between headlands having an area greater than that of a semicircle. If they do not exceed 24 nautical miles (44 km) between headlands then they are internal waters; if their entrance is wider, then that portion landward of a 24 nautical mile straight line that touches opposite low-water marks across the bay positioned to contain the greatest water area are internal waters. All archipelagic waters within the outermost islands of an archipelagic state like Indonesia or the Philippines are also considered internal waters.
Control over a contiguous zone an additional 12 nautical miles beyond its 12 nautical mile territorial sea (totaling 24 miles from shore) is permitted by a coastal nation to "prevent infringement of its customs, fiscal, immigration or sanitary laws and regulations", which the United States invoked on 24 September 1999 . Thus a coastal nation has total control over its internal waters, slightly less control over territorial waters, ostensibly even less control over waters within the contiguous zone, and supposedly no control whatsoever over an ocean beyond them.
Territorial waters claimed by one state are often disputed by another state. Territorial waters have often been subject to arbitrary extension in order to encompass activities such as offshore oil exploration, fishing rights (see Cod War) and to prevent pirate radio broadcasting from artificial marine fixtures and anchored ships.
From the 18th century until the mid 20th century, the territorial waters of the British Empire, the United States, France, and many other nations were three nautical miles (6 km) wide. Originally, this was the length of a cannon shot, hence the portion of an ocean that a sovereign state could defend from shore. However, Norway claimed four nautical miles (7 km) and Spain claimed six nautical miles (11 km) during this period.
Throughout this page, the numbers of nautical miles are exact legal definitions, whereas the numbers of kilometres are only rough approximations which do not appear in any law or treaty.
== See also ==
*International waters
*Exclusive economic zone
*Internal waters
== External link ==
*UN Convention on the Law of the Sea
Category:Law of the sea
Category:Human geography