Carcavelos: A Vital Hub for Global Submarine Cable Connectivity

Geometry of the Location: Depths, Shores, Shipping

Carcavelos, located near Lisbon, Portugal, has become one of the key hubs of submarine cable infrastructure. The geography of this area is unique: the Atlantic Ocean coastline here is relatively smooth, and the depths allow for safe cable laying as they approach the shore. However, the main reason for the concentration of cables is Portugal's geopolitical and economic position. The country sits at the crossroads of routes between Europe, Africa, and the Americas. As a result, cables connecting these regions inevitably converge in a narrow corridor near Carcavelos.

Shipping in this area also plays a role. The Port of Lisbon is one of the largest in Europe, requiring careful coordination during cable laying to avoid intersecting maritime routes. Additionally, proximity to the capital ensures convenient access to terrestrial infrastructure needed to connect cables to European networks.

What's Packed In: 16 Cables and Their Routes

Carcavelos is home to 16 submarine cables, including major routes connecting multiple continents. Among them:

• 2Africa (45,000 km): One of the longest cables in the world, connecting Europe, Africa, and Asia.
• Africa Coast to Europe (ACE) (17,000 km): Links 20 countries along Africa's west coast to Europe.
• Equiano (15,000 km): A cable connecting Europe with Southern and Western Africa.
• Europe India Gateway (EIG) (15,000 km): A route between Europe, the Middle East, and India.
• West Africa Cable System (WACS) (14,530 km): Connects Southern Africa to Europe via Africa's west coast.
• Other cables, such as SAT-3/WASC (14,350 km), Medusa Submarine Cable System (8,760 km), and MainOne (7,000 km), complement this complex network.

These cables provide connectivity between dozens of countries, including Portugal, Spain, South Africa, Egypt, Saudi Arabia, Angola, Libya, Nigeria, and others.

Alternative Corridors: Why They Don't Solve the Problem

Although alternative routes for cable laying theoretically exist, their use comes with several challenges. For example, laying cables through deeper Atlantic waters significantly increases project costs. Additionally, such routes may be less protected and more prone to damage from natural factors like underwater earthquakes or landslides.

Another option is routing through the Mediterranean Sea and the Strait of Gibraltar. However, this route is already congested with cables like SEA-ME-WE and AAE-1, and adding new lines could create additional risks and technical complexities. Thus, Carcavelos remains the optimal choice for most operators, despite its vulnerability as a chokepoint.

Breakage Scenario Step by Step

A cable break near Carcavelos could have serious consequences for global connectivity. In the first hours following the incident, traffic would begin rerouting through backup paths, leading to increased latency (RTT) and reduced bandwidth. For example, a break in the 2Africa cable could impact connections between Europe and Africa, increasing response times by several tens of milliseconds.

Within the first 24 hours, operators would start analyzing damage data and planning repair work. However, due to the high concentration of cables in this area, access for repair vessels could be challenging. If the damage is complex, restoring connectivity could take weeks, resulting in significant economic losses for countries reliant on these routes.

What GeoCables Monitors

GeoCables actively monitors the situation in the Carcavelos area. We track the status of all 16 cables, including major routes like 2Africa, ACE, and Equiano. Over the past 30 days, two anomalies in latency (RTT) have been recorded on these lines, indicating temporary disruptions. Additionally, we monitor ship movements in this zone to minimize the risk of accidental cable damage from anchors or trawls.

Carcavelos remains a vital link in global telecommunications infrastructure, and its geographic position makes it virtually irreplaceable. As the world's dependence on internet connectivity grows, ensuring the stability and security of this chokepoint becomes a key task for operators and international organizations.