Mayrit Tunnel Boring Machine: 5,200 Meters Under Madrid in Two Years 2026

The Mayrit tunnel boring machine has begun excavating a 5,200-meter tunnel beneath Madrid as part of the Metro L11 extension, with a tight two-year deadline to complete the gallery by the end of 2027. The machine started on March 26 and has already advanced 200 meters in just over a month, according to the Consejería de Transportes e Infraestructuras de la Comunidad de Madrid.

This project is critical for improving public transit in the Spanish capital, connecting the southwestern neighborhoods and reducing traffic congestion. The Mayrit TBM's progress will determine whether the L11 transformation stays on schedule.

What Is the Mayrit Tunnel Boring Machine?

The Mayrit TBM is a massive piece of equipment, measuring 98 meters in length. It was assembled specifically for this project and is now operating under Madrid's subsoil. The machine is designed to excavate tunnels efficiently while simultaneously installing the final concrete lining.

Its cutting wheel is equipped with 54 discs, 172 picks, and 24 scrapers that grind through the ground. As it advances, the machine places rings of concrete segments (dovelas) to form the tunnel's permanent structure. This integrated approach speeds up construction and improves safety.

How Fast Can the Mayrit TBM Go?

During its first month, the Mayrit TBM moved slower than expected because it was still in the adjustment phase. The first 200 meters were bored while the machine was essentially in "break-in" mode. Now, however, it is expected to reach cruising speed: between 400 and 500 meters per month, equivalent to about 15 meters per day.

At that rate, the machine could complete the 5,200-meter tunnel in roughly 10 to 13 months of full operation, but the two-year timeline includes setup, maintenance, and potential delays. The project team remains optimistic but cautious.

What Else Happens Underground?

Besides excavating, the Mayrit TBM is a mobile factory. It extracts approximately 3,500 tons of earth per day through conveyor belts that extend to the surface. There, about 150 trucks transport the material to landfills and disused mining operations.

The machine also continuously installs the concrete segment rings that line the tunnel. This dual function—excavation and lining—is what makes TBMs so efficient compared to traditional drilling and blasting.

Why the L11 Extension Matters for Madrid

The L11 extension aims to transform the metro line into a key artery for the city, improving connectivity between the southwest and the center. Once completed, it will provide faster, more reliable service for thousands of residents and help reduce car usage.

The project also includes new stations and improved accessibility features. The tunnel under Madrid Río is a crucial segment that will link existing and future stations. The background to this story is set out in Madrid Metro Line 11 Tunneling: Mayrit Nears Atocha After 3 km. A related thread runs through Madrid A-5 Tunnel: Excavation Ends May 25, Full Opening in December. Earlier coverage in SNP's Second Independence Referendum Campaign Has Already Begun shows how the argument developed.

Key Takeaways

• The Mayrit TBM must excavate 5,200 meters by the end of 2027.
• After a slow first month, it is expected to advance 400-500 meters monthly.
• The machine extracts 3,500 tons of earth daily and installs concrete lining.
• The L11 extension will enhance metro connectivity in Madrid.
• Meeting the deadline requires consistent performance and minimal downtime.

Mayrit TBM Specifications

What to Watch Next

All eyes will be on the Mayrit TBM's monthly progress reports. Any significant downtime—due to mechanical issues, ground conditions, or logistics—could jeopardize the 2027 deadline. The project team will need to maintain a steady pace and address challenges quickly. A closer look at the same subject appears in 120 Roman Inscriptions Found in Valencia Cave at 200 Meters Deep. Anyone following the wider picture can start with Madrid's La Moraleja Luxury Urbanization Fights 47-Meter Power Tower. The same theme surfaces in Car: latest articles, which takes a different angle.

Additionally, the transportation of excavated material via 150 trucks daily raises questions about traffic and environmental impact. Authorities will need to manage these concerns to maintain public support. Context on how this played out before sits in Madrid Metro TBM Mayrit Hits Palos de la Frontera Early. A companion piece, Roman Camp Discovered in Swiss Alps at 2,200 Meters, approaches the same subject from another angle.