Enclave and exclave

Explanatory diagram of territorial discontinuities: Enclaves and exclaves

Different territories (countries, states, counties, municipalities, etc.) are represented by different colours and letters; separated parts of the same territory are represented by the same colour and letter, with a different number added to each smaller part of that territory (the main part is identified by the letter only).

A:
- possesses 5 exclaves (A1, A2, A3, A4, and A5): it is impossible to go from the main part of A to any of these parts going only through territory of A; however:
  - A1 and A2 are not enclaves: neither of them is surrounded by a single "foreign" territory;
  - A1 is a semi-enclave and a semi-exclave: it has an unsurrounded sea border;
  - A2 is an exclave of A: it is separated from A;
  - A3 is an enclave: it is totally surrounded by B;
  - A4 and A5 are counter-enclaves (also known as second-order enclaves): territories belonging to A that are encroached inside the enclave E;
- contains 1 enclave (E): "foreign" territory totally surrounded by territory of A;
- contains 1 counter-counter-enclave, or third-order enclave (E1).
B:
- contains 2 enclaves (A3 and D).
C:
- continuous territory, contains no enclave or exclave
D:
- is an enclaved territory: it is territorially continuous, but its territory is totally surrounded by a single "foreign" territory (B).
E:
- is an enclaved territory: it is inside A;
- contains 2 enclaves (A4 and A5), which are counter-enclaves of A;
- possesses 1 counter-enclave (E1), which is a counter-counter-enclave as viewed by A and contained within A5.

In topological terms, A and E are each (sets of) unconnected surfaces, and B, C and D are connected surfaces. However, C and D are also simply connected surfaces, while B is not (it has first Betti number 2, the number of "holes" in B).

An enclave is a territory that is entirely surrounded by the territory of only one other state or entity. An enclave can be an independent territory or part of a larger one.^[1] Enclaves may also exist within territorial waters.^[2]^: 60 Enclave is sometimes used improperly to denote a territory that is only partly surrounded by another state.^[1] Enclaves that are not part of a larger territory are not exclaves, for example Vatican City and San Marino (both enclaved by Italy) and Lesotho (enclaved by South Africa) are enclaved sovereign states.

An exclave is a portion of a state or district geographically separated from the main part, by some surrounding alien territory.^[3] Many exclaves are also enclaves, but not all: an exclave surrounded by the territory of more than one state is not an enclave.^[4] The Azerbaijani exclave of Nakhchivan is an example of an exclave that is not an enclave, as it borders Armenia, Turkey and Iran.

Semi-enclaves and semi-exclaves are areas that, except for possessing an unsurrounded sea border (a coastline contiguous with international waters), would otherwise be enclaves or exclaves.^[4]^: 116^[5]^: 12–14 Semi-enclaves and enclaves are mutually exclusive. Likewise, semi-exclaves and exclaves are mutually exclusive. Enclaves and semi-enclaves can exist as independent states (Monaco, The Gambia and Brunei are semi-enclaves), while exclaves and semi-exclaves proper always constitute just a part of a sovereign state (like the Kaliningrad Oblast).^[4]

A pene-exclave is a part of the territory of one country that can be conveniently approached—in particular, by wheeled traffic—only through the territory of another country.^[6]^: 283 Pene-exclaves are also called functional exclaves or practical exclaves.^[5]^: 31 Many pene-exclaves partially border their own territorial waters (i.e., they are not surrounded by other nations' territorial waters), such as Point Roberts, Washington, and Minnesota's Northwest Angle. A pene-exclave can also exist entirely on land, such as when intervening mountains render a territory inaccessible from other parts of a country except through alien territory. A commonly cited example is the Kleinwalsertal, a valley part of Vorarlberg, Austria, that is accessible only from Germany to the north.

	Enclave	Exclave	Semi-enclave	Semi-exclave	Both enclave and exclave	Enclave but not exclave	Exclave but not enclave	Both semi-enclave and semi-exclave	Semi-enclave but not semi-exclave	Semi-exclave but not semi-enclave
Number of distinct alien territory^[a] bordered	1^[b]	≥1	1	≥1	1	1	>1	1	1	>1
Belongs to a larger territory	Maybe	Yes	Maybe	Yes	Yes	No	Yes	Yes	No	Yes
Has unsurrounded sea border(s)^[c]	No	No	Yes	Yes	No	No	No	Yes	Yes	Yes

^ ^a ^b Raton, Pierre (1958). "Les enclaves". Annuaire Français de Droit International. 4: 186. doi:10.3406/afdi.1958.1373.
^ Cite error: The named reference Melamid was invoked but never defined (see the help page).
^ "Exclave". Webster's Encyclopedic Unabridged Dictionary of the English Language. 1989. p. 497.
^ ^a ^b ^c Rozhkov-Yuryevsky, Yuri (2013). "The concepts of enclave and exclave and their use in the political and geographical characteristic of the Kaliningrad region". Baltic Region. 2 (2): 113–123. doi:10.5922/2079-8555-2013-2-11.
^ ^a ^b Cite error: The named reference EV was invoked but never defined (see the help page).
^ Robinson, G. W. S. (September 1959). "Exclaves". Annals of the Association of American Geographers. 49 (3, [Part 1]): 283–295. doi:10.1111/j.1467-8306.1959.tb01614.x. JSTOR 2561461.

Cite error: There are <ref group=lower-alpha> tags or {{efn}} templates on this page, but the references will not show without a {{reflist|group=lower-alpha}} template or {{notelist}} template (see the help page).

[Raton-1] Raton, Pierre (1958). "Les enclaves". Annuaire Français de Droit International. 4: 186. doi:10.3406/afdi.1958.1373.

[Melamid-2] Cite error: The named reference Melamid was invoked but never defined (see the help page).

[Websters_p497-3] "Exclave". Webster's Encyclopedic Unabridged Dictionary of the English Language. 1989. p. 497.

[YRY-4] Rozhkov-Yuryevsky, Yuri (2013). "The concepts of enclave and exclave and their use in the political and geographical characteristic of the Kaliningrad region". Baltic Region. 2 (2): 113–123. doi:10.5922/2079-8555-2013-2-11.

[EV-5] Cite error: The named reference EV was invoked but never defined (see the help page).

[Robinson-6] Robinson, G. W. S. (September 1959). "Exclaves". Annals of the Association of American Geographers. 49 (3, [Part 1]): 283–295. doi:10.1111/j.1467-8306.1959.tb01614.x. JSTOR 2561461.

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