Overview - A long-discussed fixed-link rail tunnel beneath the Strait of Gibraltar—intended to connect southern Spain with northern Morocco—has made recent progress toward realisation following new feasibility and planning activities. The project is often referenced in the media as a £7.4 billion (£≈8.5 billion / €8.5 billion) endeavour, reflecting recent cost estimates for the core undersea tunnel component. 

Feasibility and Technical Assessment

• A feasibility study commissioned by the Spanish government (October 2025) and conducted by German tunnelling specialists Herrenknecht concluded that the concept of an undersea rail tunnel linking Europe and Africa is technically viable with current tunnelling technology.
• The study specifically evaluated the engineering challenges of drilling beneath the Camarinal Threshold, a geologically complex section of the Strait. 

Project Concept and Design Parameters

• Route: Between Punta Paloma (Cádiz), Spain and Cape Malabata (near Tangier), Morocco.
• Length: Approx. 26 miles (≈42 km) overall, with around 17 miles (≈27 km) submerged underwater.
• Configuration: Planned as two separate railway bores, each carrying traffic in one direction, enabling both passenger high-speed rail and freight services.
• Depth: Tunnel bore depths could reach roughly 420 m below sea level, significantly deeper than the Channel Tunnel’s maximum depth of around 74 m.

Under current proposals, the undersea section would be part of a wider continental rail link connecting high-speed services from Madrid through Algeciras, across the tunnel, and onward into Morocco’s rail network, potentially extending toward Casablanca. 

Timeline and Planning

• Blueprint Development: Spanish consultancy Ineco has been tasked with preparing a detailed project blueprint by 2027. Government approval for advancing to fieldwork and construction phases is envisaged as early as that year.
• Fieldwork Start: Subject to approvals, fieldwork could begin around 2030, with major construction phases potentially between 2035 and 2040. These dates are preliminary and dependent on further design, financing, and cross-government agreement. 

Cost and Funding

• Recent engineering assessments align the core tunnel cost estimate at around £7.4 billion (approximately €8.5 billion).
• Additional studies suggest broader project costs could vary depending on alignment, infrastructure scope, environmental mitigation, and integration with national rail networks. 

Outstanding Issues and Next Steps

• Government Decisions: Formal approval from the governments of Spain and Morocco will be needed to proceed beyond feasibility and detailed design.
• Geotechnical and Environmental Challenges: Complex geology, deep subsea conditions, and environmental protections under the Strait remain significant challenges requiring detailed analysis in subsequent studies.
• Funding and Procurement: Securing multilateral financing or sovereignty agreements to underwrite the project’s multibillion-euro cost remains unresolved. 

Summary

The proposed Strait of Gibraltar rail tunnel linking Europe and Africa has progressed beyond conceptual discussion, with recent technical studies affirming its viability. Planned as a long undersea rail link capable of high-speed passenger and freight traffic, the project now faces detailed design, environmental planning, and governmental approval stages. Anticipated fieldwork could commence in the early 2030s, with main construction still several years away. 09/26.