Territorial waters

[2] Vessels have different rights and duties when passing through each area defined by the United Nations Convention on the Law of the Sea (UNCLOS), one of the most ratified treaties.

[3] Normally, the baseline is the low-water line along the coast as marked on large-scale charts that the coastal state recognizes.

In this case, a bay is defined as "a well-marked indentation whose penetration is in such proportion to the width of its mouth as to contain land-locked waters and constitute more than a mere curvature of the coast.

The contiguous zone is a band of water extending farther from the outer edge of the territorial sea to up to 24 nautical miles (44.4 km; 27.6 mi) from the baseline.

Unlike the territorial sea, there is no standard rule for resolving such conflicts and states must negotiate a compromise.

Before the convention, coastal nations arbitrarily extended their territorial waters to attempt to control activities that are now regulated by the exclusive economic zone, such as offshore oil exploration or fishing rights (see Cod Wars).

The outer limit of a country's continental shelf cannot stretch beyond 350 nautical miles (650 km; 400 mi) of the baseline or beyond 100 nautical miles (190 km; 120 mi) from the 2,500 metres (8,200 ft) isobath, which is a line connecting the depths of the seabed at 2,500 meters.

The Commission then validates or makes recommendations on the scientific basis for the extended continental shelf claim.

Validated extended continental shelf claims overlapping any demarcation between two or more parties are decided by bilateral or multilateral negotiation, not by the commission.

Originally, this was the distance of a cannon shot, hence the portion of an ocean that a sovereign state could defend from shore.

During the League of Nations Codification Conference in 1930, the issue of establishing international legislation on territorial waters was raised, but no agreement was reached.

[11] Claims by legislation to the adjacent continental shelf and fishing was first made by the United States government immediately following the Second World War.

On 28 September 1945, US President Harry S. Truman issued two proclamations that established government control of natural resources in areas adjacent to the coastline.

[10] It was only at the UNCLOS III (1973-1982) conference, whose provisions did not come into force until 1994, that this issue was resolved at twelve nautical miles.

Pirate radio broadcasting from artificial marine fixtures or anchored ships can be controlled by the affected coastal nation or other nations wherever that broadcast may originate, whether in the territorial sea, exclusive economic zone, the continental shelf or even on the high seas.

Throughout this article, distances measured in nautical miles are exact legal definitions, while those in kilometres are approximate conversions that are not stated in any law or treaty.

Schematic map of maritime zones (aerial view).
Maritime territory and Exclusive economic zone of some Southeast Asia and Pacific countries
Peru claims territorial waters out to 200 nmi.