Meta is building one of the world’s biggest undersea cable networks—it’s just one piece of a growing seafloor empire spanning 6 continents

Meta, the social media giant, is constructing one of the largest undersea cable networks in the world, expanding its presence in a realm less known to the public but essential for its operations. Recently, on September 21, Meta unveiled Petal, a roughly 4,300-mile subsea cable connecting the United States and France. Scheduled to become operational in 2029, Petal is set to deliver petabit-scale capacity, a feat that surpasses the capacity of today's advanced transoceanic cables by a factor of two.

This capacity, equivalent to 1 petabit per second, or approximately 125,000 gigabytes per second, would enable three-quarters of the global population to stream music simultaneously. Achieving such impressive capacity, Meta employs two-core fiber, a technology allowing two light paths within each strand, thereby doubling capacity without a corresponding rise in power or physical infrastructure demands.

While such undertakings seldom garner headlines amidst AI model and app discussions, they are the unseen backbone supporting these technologies. Meta's AI agent, Muse, launched on September 8, quickly ascended to the top of Apple's U.S. App Store within two weeks, outpacing ChatGPT. Despite questions regarding the agent's data access requirements, it operates efficiently due to the seamless data movement facilitated by Meta's subsea cables.

Meta has been actively involved in expanding its subsea cable network for over a decade, investing in more than 20 projects to date. These projects span six continents, excluding Antarctica. Among the most significant is Project Waterworth, announced in February 2025, which aims to be the longest undersea cable network, stretching over 31,000 miles and connecting the United States, Brazil, South Africa, India, and other regions across five continents.

Notably, Meta is taking a more hands-on approach to these projects. The Petal cable is developed in partnership with NEC and Sumitomo Electric Industries from Japan, with Orange handling the landing on France's Atlantic coast. Interestingly, Meta has also collaborated with rivals in the past. The MAREA cable, linking Virginia and Spain, was a joint venture with Microsoft and Telxius, demonstrating Meta's willingness to work with various entities to achieve its goals.

Despite the substantial costs associated with these projects, Meta expects its capital expenditures to reach between $130 billion and $145 billion this year, nearly double the $72.2 billion spent in 2025. As Meta continues to invest heavily in its infrastructure, it remains to be seen whether these investments will yield the anticipated returns.