IAS NOVA Interactive Atlas · Geography Through Maps
THE CHOKEPOINT ATLAS
23 straits, canals & channels for UPSC, State PSC, SSC, AP Human Geography & more — hover any marker.
Boundaries of India as per Government of India / Survey of India · volumes are approximate estimates
ALL 23 CHOKEPOINTS
Oil chokepoints
Canals
Trade arteries
India’s waters
Flashpoints & passages
The atlas above plots all 23 must-know straits, canals and channels on a real projected world map — boundaries of India as per the Survey of India. Hover (or tap) any marker for its connections, bordering countries, width, trade volume and the one fact examiners love. Filter to revise category-wise; open the Index for a rapid-fire location drill.
Test Yourself: Prelims-Style MCQs
Q1. The Ten Degree Channel separates:
The Ten Degree Channel, on the 10°N parallel, separates the Andaman Islands (north) from the Nicobar Islands (south). Lakshadweep–Maldives separation is the Eight Degree Channel.
Q2. The ‘Malacca Dilemma’ refers to which country’s strategic vulnerability?
Coined for China’s dependence on the Strait of Malacca, through which the bulk of its energy imports pass — a lane its navy does not control.
Q3. The Montreux Convention (1936) governs passage through:
The Montreux Convention gives Turkey control over warship passage through the Bosporus and Dardanelles — invoked most recently in 2022.
Q4. Which strait is preferred by supertankers too large for the Strait of Malacca?
The Lombok Strait is deep (250 m+) throughout, so ‘post-Malaccamax’ vessels take the Lombok–Makassar route. Sunda is shallow and hazardous; Palk is under 9 m deep.
Q5. The Strait of Hormuz lies between:
Iran sits on its northern shore, Oman’s Musandam exclave on the southern. Yemen–Djibouti flank Bab-el-Mandeb instead.
Q6. Adam’s Bridge (Ram Setu) is located at the mouth of the:
The chain of shoals sits between Palk Bay and the Gulf of Mannar, in the Palk Strait region between Tamil Nadu and Sri Lanka — the focus of the Sethusamudram debate.
Complete Reference: All 23 Straits, Canals & Channels
Every chokepoint from the map, with full details — bookmark this as your revision list.
Oil chokepoints
Strait of Hormuz
Connects: Persian Gulf ↔ Gulf of Oman / Arabian Sea
Bordering countries: Iran (north) · Oman’s Musandam exclave (south), UAE adjacent
Width: ~33 km at its narrowest; two 3-km shipping lanes
Traffic / trade volume: ~21 million barrels of oil/day — about one-fifth of global petroleum consumption — plus ~20% of the world’s LNG (Qatar)
Why it matters: The planet’s most critical oil chokepoint, with no pipeline network capable of fully bypassing it. Iran has repeatedly threatened closure; even the threat moves global prices.
Strait of Malacca
Connects: Andaman Sea (Indian Ocean) ↔ South China Sea (Pacific)
Bordering countries: Malaysia & Singapore (east) · Indonesia/Sumatra (west)
Width: Just ~2.8 km at Phillips Channel near Singapore
Traffic / trade volume: 90,000+ vessels and ~24 mb/d of petroleum — about a quarter to a third of all traded goods
Why it matters: The shortest sea route between East Asia and the Middle East/Europe. China’s dependence on it is called the ‘Malacca Dilemma’. Ships too big to fit are classed ‘post-Malaccamax’.
Bab-el-Mandeb
Connects: Red Sea ↔ Gulf of Aden (route to Suez)
Bordering countries: Yemen (northeast) · Djibouti & Eritrea (southwest)
Width: ~26–30 km; Perim Island splits it into two channels
Traffic / trade volume: ~9% of seaborne petroleum (~8.8 mb/d before 2024) and most Asia–Europe container traffic
Why it matters: Arabic for ‘Gate of Tears’. Houthi attacks from late 2023 forced carriers around the Cape of Good Hope — adding 10–14 days per voyage.
Turkish Straits (Bosporus + Dardanelles)
Connects: Black Sea ↔ Sea of Marmara ↔ Aegean/Mediterranean
Bordering countries: Turkey on both shores; Istanbul sits astride the Bosporus
Width: Bosporus: ~700 m — the world’s narrowest strait used for international navigation. Dardanelles: ~1.2 km
Traffic / trade volume: ~41,000 vessels/yr; ~3 mb/d of Russian & Kazakh crude, plus grain
Why it matters: Governed by the 1936 Montreux Convention, which lets Turkey restrict warships — invoked in 2022. The only maritime exit for every Black Sea nation.
Canals
Suez Canal
Connects: Mediterranean Sea ↔ Red Sea
Bordering countries: Egypt (both banks)
Width: 193 km long; sea-level, no locks
Traffic / trade volume: ~12–15% of global trade and ~30% of container traffic in a normal year; ~22,000 transits
Why it matters: Opened 1869; doubled in 2015. When the Ever Given wedged across it in March 2021, an estimated $9–10 billion of trade sat idle each day.
Panama Canal
Connects: Atlantic (Caribbean) ↔ Pacific Ocean
Bordering countries: Panama
Width: ~82 km; lock-based, climbing over Gatún Lake
Traffic / trade volume: ~5% of global maritime trade; ~13,000–14,000 transits a year
Why it matters: Opened 1914, expanded 2016. Each transit flushes ~200 million litres of freshwater to sea — which is why droughts force cuts in daily crossings.
Trade arteries
Strait of Gibraltar
Connects: Atlantic Ocean ↔ Mediterranean Sea
Bordering countries: Spain & British Gibraltar (north) · Morocco & Spanish Ceuta (south)
Width: ~13–14 km at its narrowest
Traffic / trade volume: 100,000+ vessel movements a year — among the busiest waterways on Earth
Why it matters: The ancients’ ‘Pillars of Hercules’. The Mediterranean evaporates faster than its rivers refill it, so the Atlantic pours in here as a permanent surface current.
Strait of Dover
Connects: English Channel ↔ North Sea
Bordering countries: United Kingdom (north) · France (south)
Width: ~33 km
Traffic / trade volume: 500–600 transiting ships a day plus ferries — the busiest shipping lane in the world
Why it matters: So congested it received the world’s first Traffic Separation Scheme (1967). The Channel Tunnel runs ~40 m beneath its seabed.
Sunda Strait
Connects: Java Sea ↔ Indian Ocean
Bordering countries: Indonesia: Java (east) · Sumatra (west)
Width: ~24 km at its narrowest; shallow and hazardous in parts
Traffic / trade volume: A secondary Malacca alternative — avoided by deep-draft giants
Why it matters: Krakatoa sits in the middle of it: the 1883 eruption was heard 4,800 km away and its tsunamis killed 36,000.
Lombok Strait
Connects: Java Sea ↔ Indian Ocean
Bordering countries: Indonesia: Bali (west) · Lombok (east)
Width: ~18–40 km, but deep — over 250 m throughout
Traffic / trade volume: The deep-water bypass for supertankers too large for Malacca
Why it matters: The Wallace Line runs through it — cross this strait and wildlife changes from Asian to Australian.
Makassar Strait
Connects: Celebes Sea ↔ Java/Flores Seas
Bordering countries: Indonesia: Borneo/Kalimantan (west) · Sulawesi (east)
Width: ~200–300 km — wide, deep, reliable
Traffic / trade volume: Northern leg of the Lombok–Makassar deep-draft route
Why it matters: Fought over in one of the Pacific War’s first naval battles (1942). Today it carries the coal and ore feeding East Asian industry.
Straits of Florida
Connects: Gulf of Mexico ↔ Atlantic Ocean
Bordering countries: USA, Florida & the Keys (north) · Cuba (south)
Width: ~150 km
Traffic / trade volume: Tanker and container lanes serving US Gulf refineries
Why it matters: The Gulf Stream is born here — the ocean river that warms Western Europe gets its first push through this strait.
Mozambique Channel
Connects: Indian Ocean, along Africa’s southeast flank
Bordering countries: Mozambique (west) · Madagascar (east)
Width: ~419 km at its narrowest — a channel more than a strait
Traffic / trade volume: The Cape route runs through it; traffic surged when Red Sea transits collapsed in 2024
Why it matters: Every ship that avoids Suez meets this water instead. Cyclone-prone, gas-rich, pirate-patrolled — the understudy pushed on stage.
India’s waters
Palk Strait
Connects: Bay of Bengal ↔ Palk Bay (Gulf of Mannar beyond Adam’s Bridge)
Bordering countries: India, Tamil Nadu (north) · Sri Lanka, Jaffna (south)
Width: ~40–85 km wide but under 9 m deep — big ships cannot pass
Traffic / trade volume: Negligible for ocean shipping; vessels must round Sri Lanka
Why it matters: Home of Ram Setu / Adam’s Bridge. The Sethusamudram dredging project has been debated for decades; Katchatheevu islet fuels fishing disputes.
Ten Degree Channel
Connects: Bay of Bengal ↔ Andaman Sea
Bordering countries: India: Andaman Islands (north) · Nicobar Islands (south)
Width: ~150 km, named for the 10°N parallel
Traffic / trade volume: Sits on the western approaches to Malacca
Why it matters: Watched by India’s only tri-service command (Port Blair). The islands are called India’s ‘unsinkable aircraft carrier’.
Nine Degree Channel
Connects: Arabian Sea lanes between Lakshadweep groups
Bordering countries: India: Minicoy (south) · main Lakshadweep islands (north)
Width: ~200 km along the 9°N parallel
Traffic / trade volume: A principal west–east lane: Gulf oil bound for Malacca funnels through
Why it matters: One of the Indian Ocean’s busiest highways: much of the oil and cargo moving between the Gulf, Suez and East Asia threads these channels, giving India a natural watch over global commerce. The Navy’s INS Jatayu base on Minicoy (2024) anchors that watch, and the Eight Degree Channel just south separates Minicoy from the Maldives.
Flashpoints & passages
Taiwan Strait
Connects: South China Sea ↔ East China Sea
Bordering countries: China, Fujian (west) · Taiwan (east)
Width: ~130 km at its narrowest
Traffic / trade volume: Nearly half the global container fleet transited it in 2022 — plus the semiconductors everything runs on
Why it matters: The world’s most-watched waterway: an informal ‘median line’, regular PLA exercises, conflict-disruption estimates in the trillions.
Korea (Tsushima) Strait
Connects: East China Sea ↔ Sea of Japan
Bordering countries: South Korea (northwest) · Japan (southeast); Tsushima Island splits it
Width: ~200 km overall
Traffic / trade volume: The energy lifeline for Japanese and Korean imports
Why it matters: Scene of the Battle of Tsushima (1905), where Japan annihilated Russia’s fleet — a shock that echoed through world politics.
Bering Strait
Connects: Bering Sea (Pacific) ↔ Chukchi Sea (Arctic Ocean)
Bordering countries: Russia, Chukotka (west) · USA, Alaska (east)
Width: ~82–85 km
Traffic / trade volume: Light but rising — gateway to the Northern Sea Route as Arctic ice retreats
Why it matters: The Diomede Islands sit mid-strait 3.8 km apart with the date line between them — Tomorrow Island and Yesterday Isle. Humans first entered the Americas across this gap.
Strait of Magellan
Connects: Atlantic ↔ Pacific, threading Tierra del Fuego
Bordering countries: Chile (almost entirely); Argentina at the eastern mouth
Width: ~570 km long, 2–32 km wide
Traffic / trade volume: Modest today, but the sheltered alternative to the ferocious Drake Passage
Why it matters: Navigated by Magellan in 1520. Before Panama (1914), this cold labyrinth was the world’s principal interoceanic route.
Kerch Strait
Connects: Black Sea ↔ Sea of Azov
Bordering countries: Crimea (west, occupied by Russia) · Russia, Taman (east)
Width: ~3.1 km at its narrowest
Traffic / trade volume: Grain and steel exports from Azov ports — now hostage to war
Why it matters: Russia’s Crimean Bridge (2018) spans it and has been attacked repeatedly since 2022. Control of this 3-km gap decides whether the Azov is an open sea or a Russian lake.
Torres Strait
Connects: Arafura Sea ↔ Coral Sea
Bordering countries: Australia, Cape York (south) · Papua New Guinea (north)
Width: ~150 km, littered with reefs and 270+ islands
Traffic / trade volume: Regional shipping under compulsory pilotage — too treacherous to freelance
Why it matters: Home of the Torres Strait Islanders, distinct from Aboriginal Australians. The 1978 boundary treaty is a masterclass in creative map-making.
Cook Strait
Connects: Tasman Sea ↔ South Pacific
Bordering countries: New Zealand: North Island · South Island
Width: ~22 km at its narrowest
Traffic / trade volume: The Wellington–Picton ferries stitch the country together
Why it matters: Among the world’s roughest ferry crossings — winds funnel between two mountainous islands. Māori name: Te Moana-o-Raukawa.
Frequently Asked Questions
What is a maritime chokepoint?
A chokepoint is a narrow strait or canal that concentrates large volumes of shipping because no easy alternative route exists. Of roughly 200 straits in the world, only a handful — such as Hormuz, Malacca, Bab-el-Mandeb, Suez and Panama — are true chokepoints whose disruption can shake global energy prices and supply chains within days.
Which straits are most important for UPSC Prelims and other exams?
For UPSC Prelims and State PSC mapping questions (BPSC, UPPCS, MPPSC, WBCS), prioritise the Strait of Hormuz, Strait of Malacca, Bab-el-Mandeb, the Turkish Straits (Bosporus and Dardanelles), Suez and Panama Canals, and India’s own waters — the Palk Strait, Nine Degree Channel, Ten Degree Channel and Eight Degree Channel. The same set anchors SSC CGL/CHSL General Awareness, CDS and NDA, AP Human Geography (Unit 4: Political Geography) in the US, and IB DP / A-Level Geography units on geopolitics and trade. Current-affairs-linked straits like Kerch and Taiwan also appear.
What is the difference between a strait, a channel and a canal?
A strait is a natural narrow waterway connecting two larger water bodies (Hormuz, Gibraltar). A channel is generally a wider natural passage (Mozambique Channel, Nine Degree Channel). A canal is man-made (Suez, Panama). All three can act as chokepoints.
Which straits and channels border India?
The Palk Strait separates Tamil Nadu from Sri Lanka; the Ten Degree Channel separates the Andaman from the Nicobar Islands; the Nine Degree Channel separates Minicoy from the main Lakshadweep group; and the Eight Degree Channel separates Minicoy from the Maldives.
Why is the Strait of Hormuz called the world’s most important oil chokepoint?
Roughly one-fifth of global petroleum consumption — about 21 million barrels per day — plus about a fifth of the world’s LNG passes through Hormuz, and no pipeline network can fully bypass it. Any threat of closure immediately moves world energy prices.
Does this map show the correct boundaries of India?
Yes. The boundaries of India on this map — including the full territories of Jammu & Kashmir and Ladakh — conform to the depiction approved by the Government of India / Survey of India.
