International Boundary Lines

International Boundary Lines are lines of separation between two countries, wherein individual governments have full authority over the land on each side. These designations on the border help us identify the dividing line between countries with territorial limits. 

The types of international boundaries are classified on distinct factors, from cultural landscape, religion, and language, to the course of a river. The symbol for international boundary is a combination of dashes and/or dots. It is not necessary that the boundary lines only split two countries; these can be between states, cities or even provinces.

What are International Boundary Lines?

The space between sovereign states is defined by an international boundary. 

• Within its borders, a single government has complete authority, which is unaffected by other governments. 
• As a result, the border represents the limit, or the furthest extent, of space over which a government has sovereignty. 
• The borders of the United States, for example, denote the space that we can define as the country or the area over which the federal government of the United States has absolute authority.
• The international border between Bangladesh and India is 4,096 kilometres (2,545 miles) in length, making it the world’s fifth-longest land boundary.
• West Bengal and Bangladesh share the  border at 2,217 kilometres. 

The Two Classifications for International Boundaries 

There are two broad systems for classifying the types of international boundaries:

1. The Functional or Genetic Classification

• A functional boundary is based on the concept of the type of association that exists between the line at the border and the evolution of the cultural topography of the country that it describes.

2. The Physical or Physiographic Classification

• A physical boundary is drawn such that it follows the natural features present in the environmental landscape.
• Examples of these natural features include mountains, lakes, and rivers.

3. Miscellaneous Factors-Based Classification 

• Geometric: Apart from the functional and physical classification, boundaries can also be drawn in a way that they follow a geometric pattern or a straight line. These are called geometric or straight-line boundaries.
• Ethnic: Boundaries that are formed to keep certain racial groups apart are known as ethnic or anthropogeographic boundaries. These may be demarcated based on various linguistic groups.
• Morphological: Drawn to follow some evident characteristics of the natural landscape, morphological boundaries tend to ‘follow’ a natural feature but are incorrectly misunderstood as a replacement for natural boundaries. 

The Genetic or Functional Classification

Following are the types of international boundaries in this category:

1. Antecedent Boundaries

• They were used before the availability of surveying and cartographic methodologies, before the expansion of the cultural terrain.
• These were formed before humans occupied the planet.
• Various travel impediments such as mountain ranges, water bodies, or even broad natural features such as forests and deserts were used to divide political territories. 
• Examples include the river Ohio, states of the USA, Canada and Alaska, Australia, etc.

2. Subsequent Boundaries

• Boundaries that were established after ‘subsequent’ settlement in a particular area were based on religious and language divisions.
• In Europe, the 1648 Treaty of Westphalia established a more territorial-based concept of the sovereign state, necessitating the delineation and demarcation of borders as well as the establishment of border facilities.
• For example, Yugoslavia was formed after the First World War via the unification of several territories.

3. Super-Imposed Boundaries

• The colonial expansion of European states in the 17th, 18th, and 19th centuries resulted in the establishment of many international boundaries that still exist today, although they were frequently drawn arbitrarily.
• The superimposed type boundaries do not comply with rules that are there for division based on society and culture.
• External pressures or the dominant units between two warring factions imposed these boundaries on communities.
• The majority of colonial frontiers in Africa fall in this category.

4. Relic Boundaries

• Boundary lines that have no political function in the present are called relic boundaries, though these may still be noticeable in our cultural landscape.
• These boundary lines are produced when a small state gets taken over by a large state. 
• Also, in cases when the state frontier boundaries are forsaken and redrawn, relic boundaries are produced.
• When it comes to archaeological preservation, relic boundaries are critical. 
• These are the lines used by archaeologists to determine where one archaeological site ends and another begins.
• The historically important Great Wall of China is an example of a relic boundary other than the Berlin Wall. It is an old boundary that still exists today, although it is not functional.

List of International Boundary Lines: Important

1. The Radcliffe Line

India–Pakistan–Bangladesh

2. The Hindenburg Line

Germany–Poland

3. The Durand Line

Pakistan–Afghanistan (1993)

4. The McMahon Line

It is an international boundary line of prime importance, proposed by Sir Henry McMahon at the famous Shimla Conference. It extends from Bhutan’s eastern border along the peak of the Himalayas till it reaches the Brahmaputra, where the river exits into the Assamese valley.

List of International Boundary Lines: Others

• The Mannerheim Line 

Between Russia and Finland

• The Medicine Line

Between Northern USA (excluding Alaska) and Canada

• The Oder–Neisse Line

Between Germany and Poland

• The 17th Parallel North

Between North and South Vietnam

• The 20th Parallel North

Between Sudan and Libya

• The 31st Parallel

Between Iraq and Iran

• The 35th Parallel

Between US–North Carolina and Georgia

• The 36th Parallel

Between Missouri and Arkansas

• The 38th Parallel

Between North Korea and South Korea

• The 40th Parallel

Between the states of Nebraska and Kansas in the United States

• The 41st Parallel

Between Colorado and Nebraska-Wyoming; Colorado – Utah

• The 42nd Parallel

Between New York and Pennsylvania

• The 43rd Parallel

Between Nebraska and South Dakota

The Symbol for International Boundary

• Various government boundaries are depicted in political maps with the use of different map colours.
• For example, the colour black is used to represent boundaries of different types like international boundaries, state boundaries etc.
• Dashes and/or dots are commonly used in different combinations to depict boundaries. 
• The symbol for international boundary is represented below:

Conclusion

To get a deeper understanding of the subject, one may read detailed explanations on the list of international boundary lines. These boundary lines have been present even before the availability of surveys and cartography techniques. By all means, these boundaries are the essence of mapping the number and layout of the territorial divisions on which all humans live. Thus, international boundary lines are essential as they encourage as well as restrain human interaction during conflict and trade and in times of war and peace.