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Oppenheim's International Law - Volume 1 Peace, 9th Edition edited by Jennings, Robert; Watts KCMG QC, Arthur (19th June 2008)

Part 2 The objects of international law, Ch.5 State territory, The Different Parts of State Territory

Sir Robert Jennings qc, Sir Arthur Watts kcmg qc

From: Oppenheim's International Law: Volume 1 Peace (9th Edition)

Edited By: Robert Jennings, Arthur Watts KCMG QC

From: Oxford Public International Law (http://opil.ouplaw.com). (c) Oxford University Press, 2015. All Rights Reserved. Subscriber: null; date: 14 November 2019

Internal waters — Territorial sea — Airspace

The Different Parts of State Territory

§ 171  Land, internal waters, territorial sea

The territory of a state consists in the first place of the land, including its subsoil, within its boundaries. To this must be added, if a state has a sea coast, certain waters which are within or adjacent to its land boundaries. These waters are of two kinds — national, or internal, waters; and territorial sea.

(1)  National or internal waters

National or internal waters consist of lakes, canals, and rivers and their mouths, ports, and harbours, sometimes waters landward of fringing islands, and some of its gulfs and bays.1 These different kinds of national, or internal or inland or interior, waters will be examined later, but must be distinguished at once from territorial sea.2 Internal waters are legally equivalent to a state’s land, and are entirely subject to its territorial sovereignty.

(p. 573) (2)  Territorial sea

This is a continuous belt of sea waters, formerly called the territorial waters, adjacent to the coast of a state and thus includes a part of the waters of bays, gulfs, and straits.

The sovereignty of a coastal state extends also to the seabed and subsoil of the territorial sea, and to the resources thereof; and to the airspace above the territorial sea.3

The distinction between national waters and territorial sea is important (a) because in territorial sea foreign states can claim for their ships certain rights of passage or transit (discussed below), whereas in national waters no such right exists; (b) because in gulfs and bays which are national waters, and on certain other indented or island-fringed coasts, the baseline for the measurement of the breadth of the territorial sea is the line where the waters cease to be national;4 and (c) because the municipal law of certain states may draw some distinction concerning the exercise of jurisdiction.

§ 172  Archipelagic waters

A number of archipelagic states, that is to say states consisting of one or more archipelagos of islands, draw straight baselines joining the outermost points of their outermost islands, and claim the waters so enclosed as ‘archipelagic waters’, which, though subject to rights of innocent passage, are under the sovereignty of the archipelagic states, as is also the airspace above those waters. The straight baselines enclosing the archipelagic waters thus form the baselines from which the territorial sea extends.1

§ 173  Airspace

A further part of a state’s territory is its territorial airspace, which consists of the airspace above its land, its national waters and its territorial sea. The territorial airspace also extends upwards to where the different legal regime of outer space begins, though where this limit may be is a question of some doubt.1

§ 174  Other areas of coastal state jurisdiction and rights

There are other maritime areas in respect of which a coastal state may enjoy either certain rights of jurisdiction, as in a contiguous zone adjacent to the territorial sea;1 or certain (p. 574) sovereign and exclusive rights as in respect of the resources of the continental shelf, its seabed and subsoil;2 or certain prior rights to jurisdiction and control, as in fishing zones;3 or certain exclusive and sovereign rights as in an ‘exclusive economic zone’.4


According to Art 8 of the Convention on the Law of the Sea 1982, ‘internal waters’ (as they are always called in the Convention) are ‘waters on the landward side of the baseline of the territorial sea’ (with the exception of the special case of archipelagic states, for which see § 214). For subterranean water, see Barberis, AFDI, 33 (1987), pp 129–62.

See § 187, and Hurst, BY, 3 (1922–23), at p 46, and also Charteris, BY, 2 (1920–21), at pp 47, 62–65.

Formerly called ‘territorial waters’, or ‘marginal belt’, or ‘maritime belt’, the territorial sea was so called in the 1956 Report of the International Law Commission (YBILC (1956), ii, pp 252ff), the Commentary on the draft articles (ibid, p 265) stated:

  1. (2)  The Commission preferred the term “territorial sea” to “territorial waters”. It was of the opinion that the term “territorial waters” might lead to confusion, since it is used to describe both internal waters only, and internal waters and the territorial sea combined. For the same reason, the Codification Conference also expressed a preference for the term “territorial sea”.’

Territorial sea is the term employed in pt II of the Convention on the Law of the Sea 1982.

For the distinction in English law, between national waters and territorial sea, see Post Office v Estuary Radio, see § 206, n 5. For the distinction in earlier English cases, compare R v Cunningham (1859) 3 Bell’s Crown Cases 86, where the whole of the Bristol Channel was stated to be within the bodies of the counties of Glamorgan and Somerset, and R v Keyn (1876) 2 Ex D 65 where, if the place of the collision (about two and a half miles from Dover beach) could have been said to be within the body of the county of Kent, no difficulty would have arisen in finding a court (not necessarily the Central Criminal Court) with jurisdiction to try the offender. The Fagernes [1927] P 311, while reversing R v Cunningham above as to the status of the Bristol Channel, does not affect the principle for which the latter decision is cited above.

See Art 2 of the Geneva Convention on the Territorial Sea and the Contiguous Zone 1958; and Art 2 of the Convention on the Law of the Sea 1982. For the historical evolution of the concept of sovereignty over the bed and subsoil of the territorial sea, see Marston, BY, 48 (1976–77), p 321.

See R v Keyn (1876) 2 Ex D 63, and O’Connell, BY, 34 (1958), pp 203ff; also Hurst, BY, 3 (1922–23), p 54.

See § 214 for details of the archipelagic waters regime.

For the regime of airspace, see § 218. For outer space, see § 362.

See Art 33 of the Convention on the Law of the Sea 1982; and § 205.

See Art 76 of the 1982 Convention; and § 314.

See § 327.

See Art 55 of the 1982 Convention; and § 328. Reference may be made to the 8th ed of this vol where § 175 was headed ‘Inalienability of parts of territory’. One example was given — the territorial sea. For this controversial question, see § 187, n 5.