Connecting the world: Subsea cables, route expansion and the UK’s place in global connectivity

Until the early 2000s, subsea cables followed a small number of established routes across the ocean bed. In the last 15 years, there has been a rapid increase in the number and geographic spread of these garden-hose sized fibre optic cables, which form the backbone of global connectivity.

One reason for change has been the new technology driving the globalisation of data. Cloud software and Artificial Intelligence (AI) have increased the demand for high bandwidth connections, as have low- latency apps like gaming and video conferencing.

The second cause is economic. As hyperscalers gained financial power, they began building their own global network instead of relying on existing routes. Over the last decade, they have become prolific builders of new subsea routes.

A third reason is sustainability. Green energy companies built new cable routes to provide connections to offshore windfarms and hydropower stations. Hyperscalers chased renewable energy sources or good climatic conditions, building new data centres across world, and cable routes to reach them.

The last factor, in both growth and changing routes, is geopolitics. Political change impacts subsea cable routes in two key ways: Regional instability, terrorism or espionage in an area drives cable construction elsewhere. Alternatively, an area’s digital growth draws new construction.

When Houthi rebels from Yemen attacked cables in the Black Sea, new interest developed in alternative routes through Kuwait and Saudi Arabia. Prompted by the digital growth of African nations, the 2Africa cable route was commissioned, opening last year.

This combination of technological change, economic growth, sustainability and political factors has changed the subsea cable network dramatically. In February 2025, there were 570 active subsea cable systems – and that’s not counting 81 more in construction.

The UK has been a hub for subsea routes since the Brett brothers laid the world’s first communication cables across the English Channel in 1850. Data hungry and technologically innovative, the mainland forms a land bridge between Atlantic, North Sea and Channel routes.

The country has 400 data centres, the second highest concentration in Europe and the third highest in the world. And the number is rising, with the International Data Corporation (IDC) predicting 50-100% megawatt growth in the UK between 2024 and 2028. In other words, the country has the means to process and distribute an increasing amount of data carried by subsea cables.

The UK is also well located in geopolitical terms. For instance, it is crucially placed for rapidly expanding Scandinavian subsea cable routes.

Because of this, subsea cable routes in UK waters have been increasing rapidly. Between 2019 and 2024 constructors completed 17 new routes connected to the UK.

This is part of a wider trend of growth. Forecasts predict that the worldwide market will swell to $32.86 billion by 2032. And this is despite technological progress in the cables themselves, which increases bandwidth.

The UK, with its need for data and established role as hub for routes, will likely be an important locus of new construction.

And seamless integration between submarine and UK terrestrial networks will be crucial to ensuring efficient, low-latency end-to-end connectivity.

Because Virgin Media has the largest network in the UK after BT Openreach, it is already connected to, or within a short distance of, around half of the UK’s subsea landing stations.

We are investing over £2Billion a year in our network; transforming our high bandwidth portfolio through pre-built, scalable and automated network architecture. This is increasing our reach and lowering delivery times.

Our national coverage and commitment to further expansion means we can rapidly link up existing or new subsea cable routes to inland locations (like data centres) or cross country to subsea routes on another coast.

And because of network density, we often provide the most direct route across the UK, creating a latency advantage for highly time-sensitive apps.

As the globalisation of data increases, Virgin Media Business Wholesale is excited to work with carriers looking for creative network solutions on UK soil.

The UK's network of subsea cables is testament to the country’s role as a forerunner in internation communications. As data hunger grows, geopolitical influence shifts, and technological innovation reshapes communications, the UK needs to respond quickly. Ongoing investment, strategic planning and international collaboration will ensure this critical infrastructure remains robust, secure, and fundamental to the UK's prosperity and influence.