In
geography, a 'quadripoint' is a point on the Earth that touches four distinct regions. Such points are often called "
four corners", from the corners of the four regions meeting there
[1]
International quadripoints
At present there are no generally recognized quadripoints involving four different countries, although a weak argument could be made that one exists at between
Namibia,
Zambia,
Zimbabwe and
Botswana at the
thalweg confluence of the
Zambezi River with the
Chobe River near
Kazungula. The various boundary definitions involved are subject to differing and disputed interpretations; only one combination of interpretations will produce a quadripoint.
[2]
[3].
Close calls
If the Kazungula case above is not accepted as a quadripoint, it is the place where tripoints are closest together, as the maximum distance between the tripoints is no more than a few hundred metres.
Where two tripoints occur very close to each other, they can look like a quadripoint on a map of insufficient resolution. For example, the
Kazakhstan/
Russia/
People's Republic of China tripoint at is only 40 km from
Friendship Peak, the Russia/
Mongolia/People's Republic of China tripoint. It may look like a quadripoint on some maps, but at more detailed resolution, it is clear that Kazakhstan and Mongolia never touch
[4].
Lake Chad, showing international borders
Although four countries border
Lake Chad, there is no quadripoint of
Chad,
Niger,
Nigeria, and
Cameroon within the lake.
Similarly, the
Gulf of Aqaba in the
Red Sea borders four countries, but does not contain a quadripoint of
Jordan,
Saudi Arabia,
Egypt, and
Israel.
Some political maps of the
South Pacific enclose many island nations within straight lines drawn along parallels of latitude or meridians of longitude, often with a maritime quadripoint for
Solomon Islands,
Tuvalu,
Kiribati, and
Nauru[5]. This is not a meaningful quadripoint, as the lines are simply cartographic conveniences to indicate which country the landmasses within it belong to; they do not correspond to international boundaries, many of which are undefined, or to
territorial waters or
Exclusive Economic Zones.
[6]
Previously existing four-country points
Between 1839 and 1919 there was a four-country point at the convergence of
Belgium,
Prussia/
Germany, the
Netherlands, and
Moresnet.
[1] [2]
From 1922 to 1991 there was a de facto quadripoint between
Iraq,
Kuwait,
Kingdom of Nejd/
Saudi Arabia and the
Saudi-Iraqi neutral zone, although precise boundaries were never specified by the three sovereign states.
Fewer than four countries
There are quadripoints where four border lines touch each other at one point, but involving fewer than four countries. This occurs with a
practical exclave which touches the main territory (or another exclave) at a single point. The Belgian enclaves H1 and H2 in
Baarle-Hertog touch each other at one such point, while the Netherlands also crosses it
[7].
Similarly, the
Austrian town of
Jungholz lies totally within Germany except that it borders Austria at one single point.
Cooch Behar in India is linked with
Bangladesh at one point.
Secondary quadripoints
A secondary quadripoint (or "quadrisecondary point") is the meeting of four political subdivisions (for example, provinces, states, or cantons). The four subdivisions may all belong to one country, or they may involve two or three different countries.
By analogy, one could speak of tertiary quadripoints ("quadritertiary points") where, for example, four different towns meet at one point. However, these are not considered particularly interesting. For example, many of the
counties of Nebraska are demarcated as squares in a grid.
Trinational
At , there appears to be a trinational secondary quadripoint: to the northwest is Russia (specifically the Russian exclave
Kaliningrad Oblast); to the northeast Lithuania; and to the southwest and southeast two Voivodships (provinces) of Poland:
Warmian-Masurian Voivodship and
Podlasie Voivodship.
At or around , there appears to be another trinational secondary quadripoint: to the north is Saudi Arabia, to the southeast is
Oman, and to the southwest two
Governorates of Yemen:
Hadhramaut Governorate to the westsouthwest and
Al Mahrah Governorate to the southsouthwest.
Binational
The three German
states Bavaria,
Saxony, and
Thuringia, do not form a quadripoint with the
Czech Republic; nevertheless it is frequently commented on.
On the border of Sweden and Norway, at , there appears to be a binational secondary quadripoint where two
Counties of Norway,
Nord-Trøndelag and
Nordland, meet two
Counties of Sweden,
Västerbotten County and
Jämtland County.
[8] [4]
National
The
Four Corners is the only point in the
United States of America where four states meet:
Colorado,
Utah,
New Mexico, and
Arizona meet at
right angles.
There has been an analogous
Four Corners in
Canada at since the creation of
Nunavut in 1999; it meets
Saskatchewan at a point, with
Manitoba and the
Northwest Territories at the other corners. Before 1999 this was a tertiary quadripoint, with Manitoba, Saskatchewan, and the then existing Northwest Territories districts of
Mackenzie and
Keewatin.
Four
provinces of the
Philippines meet at a point on
Mindanao island, probably at one of the three peaks of
Mount Apo:
Bukidnon,
Davao del Norte,
Davao del Sur, and
Cotabato.
There are two quadripoints in
Switzerland where three
cantons meet. At each, a
practical exclave of one canton touches its parent, while two other cantons touch each other. One is near , where the
municipality of
Roggenburg is cut off from its parent
Basel-Country by
Jura to the south and
an exclave of
Solothurn to the north. The other is near where Jura again touches Solothurn, cutting off the municipality of
Schelten from its parent
canton of Bern.
[9]
United Kingdom
An analysis of
county quadpoints in the
United Kingdom is complicated by the fact that the borders and numbers of counties have changed several times in the last century (see
Administrative counties of England).
One quadripoint has survived all the changes, lying just south west of
Stamford – where
Rutland,
Lincolnshire,
Cambridgeshire and
Northamptonshire meet. () Following the
changes of 1974, the Stamford quadpoint was unchanged. The 1995
Unitary Authority boundary changes mean that the Cambridgeshire side of the point is now officially in the Unitary Authority of
Peterborough, but the situation is otherwise unchanged.
Near
Evenlode in
Gloucestershire, is "Four Shire Stone"
[10], formerly at an intersection of Gloucestershire,
Oxfordshire,
Warwickshire, and a detached fragment of
Worcestershire. However, the fragment has been reassigned, leaving only a tripoint around ten miles (16 km) from modern Worcestershire.
[11]
In addition there are a few near misses. Near
East Grinstead, the
East Sussex-
West Sussex-
Surrey and East Sussex-Surrey-
Kent tripoints are only a mile apart. Similarly the
Staffordshire-Warwickshire-
Leicestershire and Warwickshire-Leicestershire-
Derbyshire tripoints are again around a mile apart. And
until 1965, the two tripoints formed by Gloucestershire, Oxfordshire,
Wiltshire and
Berkshire near
Lechlade came very close to one another. ().
Five or more regions
Mayon volcano, with converging administrative boundaries marked in grey.
At subnational level, one can find even more than four divisions converging at a point.
Tertiary five point:
★ Five
counties in Florida meet within
Lake Okeechobee[12]:
Okeechobee,
Martin,
Palm Beach,
Hendry, and
Glades.
★ In the Philippines:
★
★ Municipalities of Tagkawayan,
Quezon Province; Labo, San Vicente and San Lorezo Ruiz,
Camarines Norte; and Del Gallego,
Camarines Sur
★
★ Cities of Cadiz, Sagay, Silay and Talisay, and municipality of Calatrava,
Negros Occidental
★
★ Municipalities of Carmen, Batuan, Bilar, Dimiao, and Valencia,
Bohol
★
★ Municipalities of San Miguel, Ubay, Alicia, Dagohoy and Pilar, Bohol
★
★ Malaybalay City, Sumilao, Baungon, Talakag and Lantapan,
Bukidnon
★
★ Municipalities of Carmen, Aleosan, Pikit and Kabacan,
Cotabato; and Pagagawan,
Maguindanao
★
★ Municipalities of Tibiao and Barbaza,
Antique; Madalag and Libacao (a close call?),
Aklan; and Jamindan,
Capiz
Tertiary six point:
★ Municipalities of Basey and Marabut,
Samar; and Balangkayan, Llorente, Balangiga and Lawaan,
Eastern Samar, Philippines
Cases of tertiary octopoints:
★ Eight municipalities or towns in
Albay,
Philippines including
Legazpi City meet on the crater of
Mayon Volcano.
★ Eight municipalities (
Aura,
Masku,
Mynämäki,
Nousiainen,
Pöytyä, city of
Turku,
Vahto &
Yläne) meet on Kuhankuono boundary mark
[13] in the
Kurjenrahka national park in
Finland Proper.
References
This article was originally translated from the Dutch-language wiki article , as of
2006-06-20 [5], with the assistance of
SystranBox online machine translation.
1. One could argue that, if one region lies on one side of a straight line border, and the other three are on the opposite side of this line, there are only three "corners" plus a straight line. However in geometry the straight line in this context would be considered to form a straight angle measuring 180°.
2. African Boundaries: A Legal and Diplomatic Encyclopaedia, , Ian, Brownlie, C. Hurst & Co., 1979, ISBN 0-903983-87-7 ; summarized at African tripoints: Botswana-Namibia-Zambia by Michael Donner / Jesper Nielsen.
3. International Law and the Protection of Namibia's Territorial Integrity, , S., Akweenda, Martinus Nijhoff, , ISBN 90-411-0412-7
4.
5. One such map is at
6.
7. See The Baarle Enclaves website, including : overview with photograph of the H1-H2 quadripoint and Map including H1 and H2 enclaves
8. an apparent nose2janontvb binational quadripoint Kallos, Aletheia
9. RECENSEMENT FÉDÉRAL DE LA POPULATION 2000: LES NIVEAUX GÉOGRAPHIQUES DE LA SUISSE, , Martin, Schuler, Swiss Federal Statistical Office, 2005,
10. Ordnance Survey grid reference for Four Shire Stone:
11. The Batsford Guide to the Industrial Archaeology of Central Southern England: Avon County, Gloucestershire, Somerset, Wiltshire, , C. A., Buchanan, Batsford, 1980,
12. Counties of Florida map from U.S. Census Bureau.
13. Kuhankuono octopoint from National Land Survey of Finland map
See also
★
Tripoint
★
Tri-state area
★
Land borders
★
Four Corners (Canada)
★
Four Corners (United States)
★
Four Corners Monument
★
Moresnet
★
List of countries that border only one other country
★
Borderless country
External links
★
Geographical Curiosities: Local Geography a larger list of quadrisecondary points, without references.
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