Important Straits and Boundary Lines — Full List with PYQs

Straits and boundary lines are two small topics that examiners treat as one. Together they produce a question in almost every paper, and the question is always the same shape — a name is given and you say which two places it separates. There is nothing to understand here and nothing to calculate; there is only a list, and the list is short. This post covers the important straits and channels first, then the boundary lines of the world, and ends with 15 real questions from past papers.

1. Important straits of the world

A strait is a narrow stretch of water joining two larger water bodies and usually separating two land masses. Learn each one by the two lands it separates, because that is exactly how the question is framed.

Three of these carry an extra fact that gets asked separately. The Strait of Malacca is the busiest shipping route in this list and the shortest sea route between the Indian Ocean and the Pacific. The Strait of Hormuz is the world's most important oil transit route. And the Bosporus is the only strait that lies inside a single country while separating two continents.

2. Channels around India

These are asked more often than the world straits in Indian exams, and candidates mix them up because the names are all numbers.

The reliable way to hold the three numbered channels is by moving south. The Ten Degree Channel is in the Andaman and Nicobar group, while the Nine Degree and Eight Degree Channels are in Lakshadweep — nine separates Minicoy from the rest of Lakshadweep, and eight separates Minicoy from the Maldives further south.

3. Boundary lines involving India

Start with these three, because they account for most of the questions asked in Indian exams.

The Durand Line is the most common trap in this section. It was drawn by a British official and it involves the subcontinent, so candidates assume it concerns India — but it separates Pakistan and Afghanistan.

Keep the two India-China terms apart as well. The McMahon Line is the line proposed in 1914 in the eastern sector, while the Line of Actual Control is the line where the two sides actually stand today, which is why news reports use the second term rather than the first.

4. Boundary lines of the world

The parallels are the easiest group because each is a number attached to one pair of countries. The two most asked are the 38th Parallel for the two Koreas and the 49th Parallel for the United States and Canada.

Among the European lines, the pair that gets confused is Maginot and Siegfried. Both are fortification lines from the same region and the same period. The Maginot Line was built by France facing Germany, and the Siegfried Line was built by Germany facing France.

5. How it is asked in exams — 15 PYQs

1. Palk Strait separates India from which country? — Sri Lanka (SSC CGL 2023)
2. Bering Strait separates which two continents? — Asia and North America (SSC CHSL 2023)
3. The Radcliffe Line is the boundary between? — India and Pakistan (SSC MTS 2023)
4. The Durand Line separates which two countries? — Pakistan and Afghanistan (RRB NTPC 2024)
5. The McMahon Line is the boundary between? — India and China (SSC CGL 2022)
6. The 38th Parallel separates? — North Korea and South Korea (SSC GD 2024)
7. The 49th Parallel is the boundary between? — USA and Canada (SSC CHSL 2024)
8. Ten Degree Channel separates? — Little Andaman and Car Nicobar (SSC CPO 2023)
9. The Strait of Gibraltar separates? — Spain and Morocco (RRB Group D 2024)
10. Eight Degree Channel lies between India and? — Maldives (SSC MTS 2024)
11. The Strait of Malacca lies between? — Malaysia and Sumatra (SSC CGL 2024)
12. The Maginot Line was built by which country? — France (RRB NTPC 2025)
13. The Strait of Hormuz connects the Persian Gulf with? — Gulf of Oman (SSC CHSL 2022)
14. Who drew the Radcliffe Line? — Sir Cyril Radcliffe (SSC GD 2023)
15. The Bosporus Strait connects the Black Sea with? — Sea of Marmara (RRB Group D 2023)

6. Quick Revision

Frequently Asked Questions

What is the difference between the McMahon Line and the Line of Actual Control?

The McMahon Line was proposed in 1914 at the Simla Convention as the boundary between India and Tibet in the eastern sector, and China has never accepted it. The Line of Actual Control is the line where Indian and Chinese forces actually stand today across the whole border. That is why news reports about the border use the second term rather than the first.

Which countries does the Durand Line separate?

Pakistan and Afghanistan. It was drawn in 1893 by Sir Mortimer Durand, a British official, and it divides the Pashtun region between the two countries. Candidates often assume it involves India because a British officer drew it, and that assumption is the most common mistake in this topic.

What is the difference between the Nine Degree and Eight Degree Channels?

Both lie near Minicoy Island in the Lakshadweep group. The Nine Degree Channel separates Minicoy from the main Lakshadweep islands to its north. The Eight Degree Channel lies further south and separates Minicoy, and therefore India, from the Maldives.

Why is the Strait of Malacca important?

It is the shortest sea route between the Indian Ocean and the Pacific Ocean, so a very large share of world shipping and energy trade passes through it. It lies between the Malay Peninsula and the Indonesian island of Sumatra, connecting the Andaman Sea with the South China Sea.

How many questions come from straits and boundary lines in exams?

Usually one question per paper in SSC and Railway exams, and sometimes two where the geography section is larger. The format almost never changes — a name is given and you identify the two places it separates. Because the list is short and fixed, this is among the easiest full marks available in geography.

For more Geography topics in simple language, see the Geography section, and for related notes try our Rivers of India post. Preparing for a specific exam? Start with the UP Lekhpal guide or join the 100 Hour GS Course.