Today, submarine cables carry 99 percent of all intercontinental communication over more than 400 submarine telecom cables spanning over 1.3 million kilometers. Individual cable lengths range from less than 100 km to almost 40,000 km with modern cables carrying 250 Tb/s of traffic. These submerged marvels of engineering erase distance, allowing the combined knowledge of humankind to be instantly—and literally—available from anywhere on Earth at any time.