The strategic approach for implementation of ERTMS aims at achieving it by 2030 along the "Core" and by 2050 along the "Comprehensive" TEN-T network, according to the Regulation 1315/2013 on TEN-T, under revision. PTC 2021-2027 includes a list of projects of strategic importance for design and deployment of ERTMS along some major lines within the Bulgarian railway network. The present TA project proposal will contribute to the maturity of ERTMS implementation, namely with the following activities included in its scope: 1. Preparation of feasibility studies The Feasibility Study should thoroughly analyze the technical aspects, the economic justification and the need to deploy ERTMS Level 2 ((ETCS, Level 2 & GSM-R/FRMCS) ) for each of the sections concerned located along the railway network. Detailed analyses and relevant documents will have to be prepared for deployment of the equipment, including: - Terms of Reference for subsequent assignment of design and construction - CBA/Analysis of socio-economic effectiveness/CEA/other applicable tool relevant during the programming period 2021-2027. - Application Forms - Documents for environmental procedures. 2. Technical Assistance for the project management and implementation 3. Publicity. The specific sections included under the scope of the project are as follows: - Sofia-Mezdra-Gorna Oryahovitsa-Kaspichan-Sindel, existing line - Radomir-Kulata, existing line - Karnobat-Sindel, existing line under modernization - Ruse-Gorna Oryahovitsa-Stara Zagora, existing line - Vidin-Medkovets-Mezdra, line under modernization. The deployment of ERTMS, level 2 in the specified sections is planned to be implemented through PTC projects by 31.12.2029. The implementation of the project is planned to start on 01.03.2024 and to be completed by 28.02.2026.