A quadripoint is a point on Earth where four distinct political territories meet. The territories can be of different types, such as national and provincial. In North America, several such places are commonly known as Four Corners. Several examples exist throughout the world that use other names.
Usage
The word quadripoint does not appear in the Oxford English Dictionary or Merriam-Webster Online, though it has been used since 1964 by the Office of the Geographer of the United States Department of State, and appears in the Encyclopædia Britannica, as well as in the World Factbook articles on Botswana, Namibia, Zambia, and Zimbabwe, dating as far back as 1990.
History
An early instance of four political divisions meeting at a point is the Four Shire Stone in Moreton-in-Marsh, England (attested in the Domesday Book, 1086, and mentioned since 969 if not 772); until 1931, it was the meeting point of the English counties of Gloucestershire, Oxfordshire, Warwickshire, and Worcestershire.
The earliest known quadripoint involving modern nation-states existed from 1817 to 1821 where the present Alabama–Mississippi state line crossed the 31st parallel border between Spain and the United States. During that period, the part of West Florida between the Pearl and Perdido rivers (which Spain still owned but the United States forcibly occupied and annexed in 1810 after belatedly claiming it as part of the Louisiana Territory purchased from France in 1803) was subdivided and allocated partly to the State of Mississippi and partly to the Territory (and later State) of Alabama. There resulted, at the intersection of demarcated boundaries, an international quadripoint of four territories, which in the United States were named (clockwise) Baldwin and Mobile counties of Alabama and Jackson and Greene counties of Mississippi, though Mobile and Jackson Counties were actually still Spanish.
Between 1839 and 1920, there was a quadripoint at the convergence of Belgium, Prussia/Germany, the Netherlands, and Moresnet at Vaalserberg. Moresnet was never truly a country but rather only a neutral territory or condominium of the Netherlands and Prussia (originally), and of Belgium and Germany (ultimately). Subsequent political changes have restored its quadripartition along municipal lines (Kelmis, Plombieres within Belgium) since 1976 (though it has also enjoyed fivefold partition along municipal lines at times).
Four-nation quadripoints
Botswana–Namibia–Zambia–Zimbabwe
Some older sources claimed that a quadripoint existed in Africa, where the borders of Namibia, Botswana, Zambia, and Zimbabwe come together at the confluence of the Cuando (also called Chobe) and Zambezi rivers. In the absence of legal clarity, it is now widely believed that instead, two separate tripoints exist about apart (but see below regarding due diligence preceding bridge construction).
The causes of this unusual border configuration lie in the Scramble for Africa. By the 1880s, the British Empire and the British South Africa Company occupied much of Southern Africa, including the Cape Colony, Rhodesia and Bechuanaland. The German Empire also began occupying African territories in the 1880s, namely German South West Africa and German East Africa. Seeking a more efficient route between these two colonies via the Zambezi River, Germany signed the Heligoland–Zanzibar Treaty with Britain in 1890, thereby gaining control of a narrow salient called the Caprivi Strip. Following the South West Africa campaign in World War I, the Union of South Africa captured and administered South West Africa, including the Caprivi Strip. In the 1960s, with the decolonisation of Africa, the remaining British colonies in Southern Africa declared their independence, including Zambia in 1964, Rhodesia (now Zimbabwe) in 1965, and Botswana in 1966. By the time of Rhodesia's declaration of independence in 1965, there were four independent sovereign states whose territorial boundaries came very close to a quadripoint: the Republic of South Africa (occupying the Caprivi Strip) to the west, the newly independent Republic of Zambia to the north; the newly independent Rhodesia to the east; and the British Bechuanaland Protectorate to the south.