From August 26th 2020 Sofia metro has been increased by 8 new stations and 8 km route. The section, provisionally called “Stage 1”, connects Hadzhi Dimitar and Krasno Selo districts through nodes of the central part of the capital.
The construction of Stage 1 lasted four years and various technologies had been used including “New Austrian tunnel method”, “Milanese method” and a tunnel-boring machine “Vitosha” in the process of building the complex central urban section.