These two tunnels through the mountain, which will each be 6.9 km long, are part of the future Brașov-Simeria railway line, from the Rhine-Danube Corridor, Brașov - Sighisoara section, subsection 2: Apața-Cața. The project is co-financed by the European Union, and the contract was signed by the National Railway Company (CFR SA) with the consortium formed by AKTOR SA - Alstom Transport SA - Arcada Company.

TBM Eleni started drilling on March 5, 2024, and is now over 530 meters deep in the mountain. TBM Varvara started drilling on May 29, 2024, and reached a depth of 350 meters.

Hundreds of precast concrete rings are installed around the clock to form the impressive tunnels that have an inner diameter of 8.4 meters and an outer diameter of 9.4 meters. A railway line will pass through each of these tunnels, shortening the current zigzag route of the train from Brașov to Sighisoara, which follows the Olt riverbed.

Eleni and Varvara are digging the southern pair of tunnels, while a second pair of tunnels, called Homorod, with a length of 5.1 km each, will be drilled between Racoș and Homorod. TBMs 3 and 4, Alexandra and Konstantina, are being assembled there and are being tested and will start drilling soon.

AKTOR Construction is a member of the Intrakat Group, an industry leader in the construction, infrastructure, concessions/public-private partnerships (PPP), renewable energy (RES), energy storage, real estate development, environmental projects and digital technologies sectors in Greece, with a significant presence in Southeast Europe, listed on the Athens Stock Exchange since 2001.