site.btaFour Trains with Advanced Equipment to Enter Service on Sofia Metro's Extended Line 3

Four Siemens trains will enter service when a 3-kilometre extension of Sofia Metro's Line 3 beneath Gen. Vladimir Vazov Boulevard opens, Sofia Municipality said on Tuesday. Mayor Vasil Terziev inspected the newly completed section ahead of the state acceptance commission's inspection.

The eastward extension to the Levski housing estate includes three Metro stations and is expected to enable more than 45,000 additional passengers a day to use the underground railway.

Mayor Terziev commented: "The Metro continues to expand. Work is progressing on schedule, and our goal is to open the new section to passengers immediately after it receives approval so that people can travel more conveniently and quickly. We are also working on the next extensions."

The new trains are equipped with advanced systems that automatically determine their location along the line and maintain constant communication with the operations control centre. Metro Line 3 uses a Communications-Based Train Control (CBTC) system, which enables fast and safe operation.

According to Sofia Municipality, Line 3 incorporates Grade of Automation 3 (GoA3) technology, allowing automated train operation with an onboard operator. The infrastructure has been designed to allow a future transition to GoA4, enabling fully automated operation.

The newly completed section will now be presented to a state acceptance commission appointed by the National Construction Control Directorate. Once approval is granted, the extension will open for regular passenger services.

Construction of the extension of Line 3 began in March 2022 and was carried out entirely underground. The project has been financed under the Recovery and Resilience Plan, with funding of BGN 282,321,041 excluding VAT, equivalent to EUR 144.3 million.

At the end of May, four new Skoda metro trains entered service on the Sofia Metro network. The new trainsets replaced some of the oldest rolling stock operating on Lines 1, 2 and 4 and will provide a more comfortable journey for passengers, Mayor Terziev said at the time.