Important Boundary Lines in the World

Name of Lines/Boundaries

Between

Features/
Description

17th
Parallel

South Vietnam and North Vietnam

The 17th latitude from the equator
divided erstwhile North and South Vietnam.

It was demarcated based on the 1954
Geneva Accords.

The 17th parallel became irrelevant
after the unification of Vietnam in 1976.

20th Parallel

Libya and Sudan

It is located at the 20th northern latitude which is used as the
border between Sudan and Libya.

22nd
Parallel

Egypt and Sudan

The 22nd latitude north of the equator
marks a major portion of the Sudan-Egypt border.

25th Parallel

Mauritania and Mali

The northernmost section of the Mali-Mauritania border is marked using
this line.

31st
Parallel

Iran and Iraq

The 31st northern latitude marks
the border between Iraq and Iran.

It also demarcates the border
between the US states of Louisiana and Mississippi.

38th Parallel

South Korea and North Korea

The 38th parallel is used to demarcate the central part of the
Demilitarized zone between North and South Korea.

49th
Parallel

The USA and Canada

It is located 49 degrees north of
the equator.

Demarcated after the Anglo-American
Convention of 1818 and the Oregon Treaty of 1846, it forms the international
border between the northern USA (Excluding Alaska) and Canada.

Blue Line

Lebanon and Israel

A border
demarcation between Lebanon and Israel was published
by the United Nations on 7 June 2000 determining whether Israel had
fully withdrawn from Lebanon.

Durand Line

Pakistan and Afghanistan

Delimited by Sir Mortimer Durand
with the agreement of the erstwhile Amir of Afghanistan in 1893.

Present-day Afghanistan does not
recognize the Durand line.

Green Line / Attila Line / UN Buffer Zone

The Republic of Cyprus and Turkish Cyprus

A demilitarized zone, patrolled by the United Nations Peacekeeping
Force in Cyprus (UNFICYP), that was established in 1964 and extended in 1974
after the ceasefire of 16 August 1974

Hindenburg
Line

Poland and Germany

It was a German Defensive line in
French territory during World War I

It was rendered irrelevant by the
treaty of Versailles in 1919.

Maginot Line

Germany and France

It was a defensive line at the French border towards Germany before
World War II. The Maginot line was rendered obsolete following the successful
invasion of France by Germany following the outbreak of World War II

Mannerheim
Line

Russia and Finland

Finland built this as a defensive
line against the Soviet Union for the Winter War during World War II.

McMahon Line

China and India

It was drawn by Sir Henry McMahon in consultation with Tibetan representatives
in 1914.

China disputes the legal status of this line but it is the de facto
border between India and China.

Oder-Neisse
Line

Poland and Germany

It runs along the rivers Oder and
Lusatian Neisse rivers.

It demarcates the Polish-German
border according to the Potsdam Conference. It was recognized by a unified
Germany in 1990.

Purple Line

Israel and Syria

The Purple line was the ceasefire line between Israel and Syria after
the 1967 war.

Radcliffe
Line

India and Pakistan

It was demarcated by Sir Cyril
Radcliffe for the Partition of India and the formation of East and West
Pakistan.

It includes present-day India,
Bangladesh, and Pakistan.

Siegfried Line

France and Germany

It was built as an extension of the Hindenburg defensive line on the
western front of World War I by the Weimar Republic and later the Third Reich
of Germany in the 1930s.