CONVENTION ON THE TERRITORIAL SEA AND THE CONTIGUOUS ZONE 

(Geneva, 29 April 1958)

ENTRY INTO FORCE : 10 SEPTEMBER 1964

Depositary :  Secretary-General of the United Nations

Summary : The Convention on the Territorial Sea and Contiguous Zone was one of the four Conventions on the law of the sea adopted at the First United Nations Conference on the Law of the Sea (UNCLOS I) in Geneva in 1958. The Convention confirmed the coastal State's right to claim a territorial sea, over which it's sovereignty extends, and sets out the principles by which the limits of the territorial sea may be determined (but does not specify a limit on the breadth of the zone). The Convention also codified the traditional right of innocent passage, whereby foreign vessels are entitled to navigate through the territorial sea (for the purposes of traversing that sea or proceeding to or from internal waters) provided that such passage is not prejudicial to the peace, good order or security of the coastal State. As regards foreign fishing vessels, the Convention expressly states that passage is not to be considered innocent if such vessels do not observe such laws and regulations as the coastal State may make and publish in order to prevent foreign vessels from fishing in the territorial sea.
The Convention also established the concept of the contiguous zone, in which the coastal State enjoys limited jurisdiction for the purpose of enforcing customs, fiscal, sanitary and immigration laws. 

THE STATES PARTIES TO THIS CONVENTION,

HAVE AGREED AS FOLLOWS: 

PART I - TERRITORIAL SEA

SECTION I - GENERAL

Article 1

1. The sovereignty of a State extends, beyond its land territory and its internal waters, to a belt of sea adjacent to its coast, described as the territorial sea. 

2. This sovereignty is exercised subject to the provisions of these Articles and to other rules of international law. 

Article 2

The sovereignty of a coastal State extends to the air space over the territorial sea as well as to its bed and subsoil. 

SECTION II - LIMITS OF THE TERRITORIAL SEA

Article 3

Except where otherwise provided in these Articles, the normal baseline for measuring the breadth of the territorial sea is the low-water line along the coast as marked on large-scale charts officially recognized by the coastal State. 

Article 4

1. In localities where the coast line is deeply indented and cut into, or if there is a fringe of islands along the coast in its immediate vicinity, the method of straight baselines joining appropriate points may be employed in drawing the baseline from which the breadth of the territorial sea is measured. 

2. The drawing of such baselines must not depart to any appreciable extent from the general direction of the coast, and the sea areas lying within the lines must be sufficiently closely linked to the land domain to be subject to the régime of internal waters. 

3. Baselines shall not be drawn to and from low-tide elevations, unless lighthouses or similar installations which are permanently above sea level have been built on them. 

4. Where the method of straight baselines is applicable under the provisions of paragraph 1, account may be taken, in determining particular baselines, of economic interests peculiar to the region concerned, the reality and the importance of which are clearly evidenced by a long usage. 

5. The system of straight baselines may not be applied by a State in such a manner as to cut off from the high seas the territorial sea of another State. 

6. The coastal State must clearly indicate straight baselines on charts, to which due publicity must be given. 

Article 5

1. Waters on the landward side of the baseline of the territorial sea form part of the internal waters of the State. 

2. Where the establishment of a straight baseline in accordance with Article 4 has the effect of enclosing as internal waters areas which previously had been considered as part of the territorial sea or of the high seas, a right of innocent passage, as provided in Articles 14 to 23, shall exist in those waters. 

Article 6

The outer limit of the territorial sea is the line every point of which is at a distance from the nearest point of the baseline equal to the breadth of the territorial sea. 

Article 7

1. This Article relates only to bays the coasts of which belong to a single State. 

2. For the purposes of these Articles, a bay is a well-marked indentation whose penetration is in such proportion to the width of its mouth as to contain landlocked waters and constitute more than a mere curvature of the coast. An indentation shall not, however, be regarded as a bay unless its area is as large as, or larger than, that of the semi-circle whose diameter is a line drawn across the mouth of that indentation. 

3. For the purpose of measurement, the area of an indentation is that lying between the low-water mark around the shore of the indentation and a line joining the low-water marks of its natural entrance points. Where, because of the presence of islands, an indentation has more than one mouth, the semi-circle shall be drawn on a line as long as the sum total of the lengths of the lines across the different mouths. Islands within an indentation shall be included as if they were part of the water areas of the indentation. 

4. If the distance between the low-water marks of the natural entrance points of a bay does not exceed twenty-four miles, a closing line may be drawn between these two low-water marks, and the waters enclosed thereby shall be considered as internal waters. 

5. Where the distance between the low-water marks of the natural entrance points of a bay exceeds twenty-four miles, a straight baseline of twenty-four miles shall be drawn within the bay in such a manner as to enclose the maximum area of water that is possible with a line of that length. 

6. The foregoing provisions shall not apply to so-called "historic" bays, or in any case where the straight baseline system provided for in Article 4 is applied. 

Article 8

For the purpose of delimiting the territorial sea, the outermost permanent harbour works which form an integral part of the harbour system shall be regarded as forming part of the coast. 

Article 9

Roadsteads which are normally used for the loading, unloading and anchoring of ships, and which would otherwise be situated wholly or partly outside the outer limit of the territorial sea, are included in the territorial sea. The coastal State must clearly demarcate such roadsteads and indicate them on charts together with their boundaries, to which due publicity must be given. 

Article 10

1. An island is a naturally-formed area of land, surrounded by water, which is above water at high-tide. 

2. The territorial sea of an island is measured in accordance with the provisions of these Articles. 

Article 11

1. A low-tide elevation is a naturally-formed area of land which is surrounded by and above water at low-tide but submerged at high tide. Where a low-tide elevation is situated wholly or partly at a distance not exceeding the breadth of the territorial sea from the mainland or an island, the low-water line on that elevation may be used as the baseline for measuring the breadth of the territorial sea. 

2. Where a low-tide elevation is wholly situated at a distance exceeding the breadth of the territorial sea from the mainland or an island, it has no territorial sea of its own. 

Article 12

1. Where the coasts of two States are opposite or adjacent to each other, neither of the two States is entitled, failing agreement between them to the contrary, to extend its territorial sea beyond the median line every point of which is equidistant from the nearest points on the baselines from which the breadth of the territorial seas of each of the two States is measured. The provisions of this paragraph shall not apply, however, where it is necessary by reason of historic title or other special circumstances to delimit the territorial seas of the two States in a way which is at variance with this provision. 

2. The line of delimitation between the territorial seas of two States lying opposite to each other or adjacent to each other shall be marked on large-scale charts officially recognized by the coastal States. 

Article 13

If a river flows directly into the sea, the baseline shall be a straight line across the mouth of the river between points on the low-tide line of its banks 

SECTION III - RIGHT OF INNOCENT PASSAGE

Sub-Section A - Rules Applicable to all Ships

Article 14

1. Subject to the provisions of these Articles, ships of all States, whether coastal or not, shall enjoy the right of innocent passage through the territorial sea. 

2. Passage means navigation through the territorial sea for the purpose either of traversing that sea without entering internal waters, or of proceeding to internal waters, or of making for the high seas from internal waters. 

3. Passage includes stopping and anchoring, but only in so far as the same are incidental to ordinary navigation or are rendered necessary by force majeure or by distress. 

4. Passage is innocent so long as it is not prejudicial to the peace, good order or security of the coastal State. Such passage shall take place in conformity with these Articles and with other rules of international law. 

5. Passage of foreign fishing vessels shall not be considered innocent if they do not observe such laws and regulations as the coastal State may make and publish in order to prevent these vessels from fishing in the territorial sea. 

6. Submarines are required to navigate on the surface and to show their flag. 

Article 15

1. The coastal State must not hamper innocent passage through the territorial sea. 

2. The coastal State is required to give appropriate publicity to any dangers to navigation, of which it has knowledge, within its territorial sea. 

Article 16

1. The coastal State may take the necessary steps in its territorial sea to prevent passage which is not innocent. 

2. In the case of ships proceeding to internal waters, the coastal State shall also have the right to take the necessary steps to prevent any breach of the conditions to which admission of those ships to those waters is subject. 

3. Subject to the provisions of paragraph 4, the coastal State may, without discrimination amongst foreign ships, suspend temporarily in specified areas of its territorial sea the innocent passage of foreign ships if such suspension is essential for the protection of its security. Such suspension shall take effect only after having been duly published. 

4. There shall be no suspension of the innocent passage of foreign ships through straits which are used for international navigation between one part of the high seas and another part of the high seas or the territorial sea of a foreign State. 

Article 17

Foreign ships exercising the right of innocent passage shall comply with the laws and regulations enacted by the coastal State in conformity with these Articles and other rules of international law and, in particular, with such laws and regulations relating to transport and navigation. 

Sub-Section B - Rules Applicable to Merchant Ships

Article 18

1. No charge may be levied upon foreign ships by reason only of their passage through the territorial sea. 

2. Charges may be levied upon a foreign ship passing through the territorial sea as payment only for specific services rendered to the ship. These charges shall be levied without discrimination. 

Article 19

1. The criminal jurisdiction of the coastal State should not be exercised on board a foreign ship passing through the territorial sea to arrest any person or to conduct any investigation in connexion with any crime committed on board the ship during its passage, save only in the following cases:

(a) If the consequences of the crime extend to the coastal State; or 

(b) If the crime is of a kind to disturb the peace of the country or the good order of the territorial sea; or 

(c) If the assistance of the local authorities has been requested by the captain of the ship or by the consul of the country whose flag the ship flies; or 

(d) If it is necessary for the suppression of illicit traffic in narcotic drugs. 

2. The above provisions do not affect the right of the coastal State to take any steps authorized by its laws for the purpose of an arrest or investigation on board a foreign ship passing through the territorial sea after leaving internal waters. 

3. In the cases provided for in paragraphs 1 and 2 of this Article, the coastal State shall, if the captain so requests, advise the consular authority of the flag State before taking any steps, and shall facilitate contact between such authority and the ship's crew. In cases of emergency this notification may be communicated while the measures are being taken. 

4. In considering whether or how an arrest should be made, the local authorities shall pay due regard to the interests of navigation. 

5. The coastal State may not take any steps on board a foreign ship passing through the territorial sea to arrest any person or to conduct any investigation in connexion with any crime committed before the ship entered the territorial sea, if the ship, proceeding from a foreign port, is only passing through the territorial sea without entering internal waters. 

Article 20

1. The coastal State should not stop or divert a foreign ship passing through the territorial sea for the purpose of exercising civil jurisdiction in relation to a person on board the ship. 

2. The coastal State may not levy execution against or arrest the ship for the purpose of any civil proceedings, save only in respect of obligations or liabilities assumed or incurred by the ship itself in the course or for the purpose of its voyage through the waters of the coastal State. 

3. The provisions of the previous paragraph are without prejudice to the right of the costal State, in accordance with its laws, to levy execution against or to arrest, for the purpose of any civil proceedings, a foreign ship lying in the territorial sea, or passing through the territorial sea after leaving internal waters. 

Sub-Section C - Rules Applicable to Government Ships other than Warships

Article 21

The rules contained in sub-sections A and B shall also apply to government ships operated for commercial purposes. 

Article 22

1. The rules contained in sub-section A and in Article 18 shall apply to government ships operated for non-commercial purposes. 

2. With such exceptions as are contained in the provisions referred to in the preceding paragraph, nothing in these Articles affects the immunities which such ships enjoy under these Articles or other rules of international law. 

Sub-Section D - Rule Applicable to Warships

Article 23

If any warship does not comply with the regulations of the coastal State concerning passage through the territorial sea and disregards any request for compliance which is made to it, the coastal State may require the warship to leave the territorial sea. 

PART II - CONTIGUOUS ZONE

Article 24

1. In a zone of the high seas contiguous to its territorial sea, the coastal State may exercise the control necessary to: 

(a) Prevent infringement of its customs, fiscal, immigration or sanitary regulations within its territory or territorial sea; 

(b) Punish infringement of the above regulations committed within its territory or territorial sea. 

2. The contiguous zone may not extend beyond twelve miles from the baseline from which the breadth of the territorial sea is measured. 

3. Where the coasts of two States are opposite or adjacent to each other, neither of the two States is entitled, failing agreement between them to the contrary, to extend its contiguous zone beyond the median line every point of which is equidistant from the nearest points on the baselines from which the breadth of the territorial seas of the two States is measured. 

PART III - FINAL ARTICLES

Article 25

The provisions of this Convention shall not affect conventions or other international agreements already in force, as between States Parties to them. 

Article 26

This Convention shall, until 31 October 1958, be open for signature by all States Members of the United Nations or of any of the specialized agencies, and by any other State invited by the General Assembly of the United Nations to become a Party to the Convention.

Article 27

This Convention is subject to ratification. The instruments of ratification shall be deposited with the Secretary-General of the United Nations.

Article 28

This Convention shall be open for accession by any States belonging to any of the categories mentioned in Article 26. The instruments of accession shall be deposited with the Secretary-General of the United Nations. 

Article 29

1. This Convention shall come into force on the thirtieth day following the date of deposit of the twenty-second instrument of ratification or accession with the Secretary-General of the United Nations.

2. For each State ratifying or acceding to the Convention after the deposit of the twenty-second instrument of ratification or accession, the Convention shall enter into force on the thirtieth day after deposit by such State of its instrument of ratification or accession. 

Article 30

1. After the expiration of a period of five years from the date on which this Convention shall enter into force, a request for the revision of this Convention may be made at any time by any Contracting Party by means of a notification in writing addressed to the Secretary-General of the United Nations. 

2. The General Assembly of the United Nations shall decide upon the steps, if any, to be taken in respect of such request. 

Article 31

The Secretary-General of the United Nations shall inform all States Members of the United Nations and the other States referred to in Article 26: 

(a) Of signatures to this Convention and of the deposit of instruments of ratification or accession, in accordance with Articles 26, 27 and 28; 

(b) Of the date on which this Convention will come into force in accordance with Article 29; 

(c) Of requests for revision in accordance with Article 30. 

Article 32

The original of this Convention, of which the Chinese, English, French, Russian and Spanish texts are equally authentic, shall be deposited with the Secretary-General of the United Nations, who shall send certified copies thereof to all States referred to in Article 26. 

IN WITNESS WHEREOF the undersigned Plenipotentiaries, being duly authorized thereto by their respective Governments, have signed this Convention. 

DONE at Geneva, this twenty-ninth day of April one thousand nine hundred and fifty-eight.