Cables may not be visible to most of us, but they form the invisible infrastructure that powers the modern world. From submarine communication cables that transmit internet traffic across oceans, to power transmission cables that deliver electricity over vast distances, cables are truly the arteries of global connectivity.
longest-undersea-cable-in-the-world
In this article, we explore the longest cables in the world, with a focus on the longest undersea cable systems and their crucial role in international communications.
The Longest Cable in the World: An Overview
When we ask about the longest cable in the world, it’s important to clarify:
Are we talking about telecommunications cables?
Or power transmission cables?
Or even railway and specialty cables?
Each serves a unique purpose, but in terms of sheer length, undersea communication cables dominate the list.
The Longest Undersea Cable Systems
1. SEA-ME-WE 6 (Southeast Asia – Middle East – Western Europe 6)
Length: ~19,200 km
Regions Connected: From Singapore to France, covering Southeast Asia, the Middle East, and Europe.
Significance: Provides high-capacity internet connectivity between three continents.
2. 2Africa Cable (Meta-led Project)
Length: ~45,000 km (once completed, expected to be the longest undersea cable system in the world)
Regions Connected: Circling the African continent, connecting Europe, the Middle East, and Asia.
Impact: Designed to dramatically expand internet access in Africa.
3. SEA-ME-WE 3 (Legacy System)
Length: ~39,000 km
Regions Connected: Asia, Middle East, Europe, and Australia.
Legacy: Once the world’s longest submarine cable system, still operational in parts.
4. Other Notable Projects
Pacific Light Cable Network (China – U.S.)
MAREA Cable (U.S. – Spain, backed by Microsoft & Meta)
Beyond Internet: The Longest Power Transmission Cables
Cables are not only about data—they also transmit electricity across borders.
NordLink (Norway – Germany): A 623 km submarine HVDC (High Voltage Direct Current) cable that transmits renewable energy.
North Sea Link (UK – Norway): 720 km, the world’s longest subsea interconnector for electricity.
Future Projects: Longer HVDC interconnectors are planned to link continents for renewable energy trade.
Why Are Long Cables Important?
✔ Global Internet: 99% of international data flows through submarine cables, not satellites.
✔ Energy Security: Long HVDC cables enable cross-border electricity trading, reducing reliance on fossil fuels.
✔ Economic Growth: Countries connected by reliable cables enjoy faster, cheaper digital infrastructure.
Challenges of Building the Longest Cables
Deep Ocean Engineering: Some cables lie 8,000 meters below sea level.
Maintenance: Repairing a broken undersea cable can take weeks.
Geopolitics: Control of cable routes often involves international negotiations.
Conclusion
The longest cable in the world is more than just a record-breaking feat of engineering—it is a critical lifeline for digital communication, renewable energy, and economic connectivity. With projects like 2Africa and next-generation HVDC interconnectors, the world is set to become even more connected in the coming decades.
👉 Whether you search for longest cable, longest cable in the world, or longest undersea cable, one truth remains: these massive infrastructures silently sustain our global way of life.
