As of 2025, there are over 600 active and planned undersea internet cables spanning the globe. 4 million kilometres (nearly 870,000 miles), enough to circle the Earth more than 35 times. Nearly all international internet traffic – from cloud workloads to streaming video – voyages along a handful of submarine fibre-optic cable highways. These undersea trunks connect continents, power the internet, and underpin the so-called AI 'supercycle' – they also make terrestrial cross-border. Undersea fiber-optic cables form the foundations of global internet connectivity, transmitting over 99% of international data traffic. These cables, composed of optical fibers encased in protective layers, stretch across oceanic floors, linking major economic centers worldwide. Data moves through. This visualization shows the growth of the undersea cable network, global internet peering capacity, and the distribution of IP addresses via BGP announcements over time. Here's why they're so important to global connectivity.
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