Technology 4 min read By Bethany Hadley
Meta to Build 4,300-Mile Petal Subsea Cable Linking US and France
Meta has announced Petal, a 4,300-mile subsea cable connecting the US and France that will be the first to deliver petabit-scale capacity across an ocean, part of a wider seafloor infrastructure push spanning six continents.
Meta is building one of the world's largest undersea cable networks, a project that will connect the United States and France and deliver record-breaking data capacity across the Atlantic. The company announced Petal on September 21, a roughly 4,300-mile subsea cable expected to enter service in 2029. According to Meta, it will be the first cable to deliver petabit-scale capacity across an ocean, carrying 1 petabit per second — about 125,000 gigabytes per second — double what today's most advanced transoceanic cables can handle.
Meta says that capacity is enough for three-quarters of the world's population to stream music simultaneously. The cable achieves this through two-core fibre, which fits two light paths inside each strand, allowing Meta to double capacity without a proportional increase in power or physical infrastructure. Petal is being developed with Japan's NEC and Sumitomo Electric Industries, while French telecom Orange is handling the landing on France's Atlantic coast.
The project is part of a broader seafloor empire Meta has assembled over the past decade. The company, now valued at roughly $1.85 trillion, says it has invested in more than 20 subsea cable projects that together touch every continent except Antarctica. The most ambitious is Project Waterworth, announced in February 2025, which Meta says will stretch more than 31,000 miles — longer than the Earth's circumference — connecting the US, Brazil, South Africa, India and other regions across five continents. Some segments will be laid as deep as roughly 4.3 miles below the surface to protect them from ship anchors and other hazards.
Meta's 2Africa system, whose core was completed last year, circles the African continent and connects to Europe, the Middle East and South Asia. Meta says it lands in 33 countries and can reach 3 billion people. The company has not built this infrastructure alone. The MAREA cable between Virginia and Spain, completed in 2017, is jointly owned with Microsoft and telecom company Telxius. Increasingly, however, Meta is taking the driver's seat. Waterworth will be wholly owned by Meta, making it only the company's third solely owned cable, according to telecom research firm TeleGeography.
These projects do not come cheap. Meta has not disclosed what Petal or Waterworth will cost, but TechCrunch reported before Waterworth's announcement that the project could top $10 billion. Even so, cables represent a small slice of Meta's overall infrastructure bill. The company expects capital expenditures of $130 billion to $145 billion this year, nearly double the $72.2 billion it spent in 2025.
The investment comes as data centres dominate headlines amid mounting local opposition over electricity bills, water use and zoning fights. Meta has been expanding its infrastructure somewhere far less visible: the bottom of the ocean. Projects like Petal rarely make headlines in an industry fixated on AI models and apps, but they are what make those products run. Meta's personal AI agent, Muse, launched on September 8 and climbed to number one on Apple's US App Store within two weeks, overtaking ChatGPT. It did so even as critics questioned how much access the agent needs to users' email, calendars and payment accounts. Muse is powered by Meta's Muse Spark models, and products like it depend on moving enormous volumes of data between Meta's data centres and its users around the world.
With 12-figure budgets and record-breaking construction projects, Meta is betting its infrastructure spending will pay off. Whether it does remains to be seen.
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