Technical details
COSEA (group of companies in charge of design and execution of the SEA line)

2007 – 2017, with ongoing maintenance services provided by SYSTRA

Project Management, Design, Testing & Commissioning , Operation & Maintenance
High Speed Rail

Travel from Paris to Bordeaux in 2 hours and 4 minutes: such was the challenge met by SYSTRA in the context of the South Europe Atlantic (SEA) high speed line project. The Tours-Bordeaux high speed rail line was 10 years in the making, launching on 2 July 2017.


The Tours-Bordeaux high speed rail line (HSL) is made up of a new 302km high speed rail link between Tours and Bordeaux in France, as well as 38km of connecting lines to the existing rail network along the corridor.

The line passes through the Centre, Poitou-Charentes, and Aquitaine regions, and six districts in the country. It reduces the journey time between Paris and Bordeaux by approximately one hour. As many as 20 million passengers can take advantage of the high-speed transport service on the line.

Project - Paris Bordeaux High Speed Rail Line


SEA was a high-stakes project calling for strong partners ready to assume their share of associated risks. Sharing the same long-term vision, SYSTRA and VINCI teamed up to imagine a new way to design and execute this project: shorter construction deadlines, strict cost management and “traffic” risk borne by the concession-holder. To date, this is the largest railway PPP (public-private partnership) signed in France (€7.8 billion), covering a 50-year period.

Within this contractual framework, the necessary resources and innovation capabilities of private-sector partners were mobilised for the development of the French railway system, all under efficient deadlines.

The project involved nearly 9,000 people, including 700 SYSTRA employees who were part of all phases, including design and delivery, project management, monitoring and coordination of construction works, operations, safety and training, and testing.

A total of 488 large structures were constructed, including all land rights-of-way, track, catenary and telecommunications systems, and a TVM 300/ERTMS level 2 double signalling system to welcome trains from all of Europe.


The SEA HSL project observes the latest European standards in terms of rail traffic, including the European Rail Traffic Management System (ERTMS), a unified signalling security and supervision system aimed at ensuring the interoperability of various national railway networks.

SEA fully complies with the commitments of the Grenelle environmental pact to promote travel to the regions and reduce greenhouse gas emissions. Travelling round-trip from Paris to Bordeaux on the HSL saves 50,000 metric tonnes of CO2 per year, as opposed to flying.


The HSL has transformed the face of transport in the west of France. With 302km of new line and trains moving at 320km/h, SEA cuts journey times by more than half and brings regions and populations closer together.

The adventure will continue until 2061: the Group has a 30% stake in the company MESEA, responsible for the maintenance of the HSL. On a daily basis, more than 200 SYSTRA employees are present on the ground to maintain the excellence of this infrastructure.