Enhancing Cross-Border Connectivity Between Bulgaria and Serbia

Introduction

The 5G Balkans project aims to develop the necessary digital backbone to support the future of autonomous transportation along the route Sofia–Dimitrovgrad (Serbia), part of the strategic Trans-European Transport Corridor “Orient/East-Med” connecting Belgrade, Sofia, and Thessaloniki.

Funded by the European Union’s Connecting Europe Facility (CEF) under Grant Agreement No. 101133895, the project focuses on creating high-speed, resilient, and future-ready infrastructure to enable safe and efficient cross-border mobility.

Business Challenge

Autonomous vehicles require ultra-reliable, low-latency communication and continuous network coverage. However, much of the existing infrastructure along the Sofia–Kalotina route (approximately 135 km) and surrounding rural regions is not yet ready to meet these demanding requirements. To support the transformation of the transport industry, it is essential to enhance fiber connectivity and ensure stable 5G-ready infrastructure across the region.

Solution

The project is jointly led by CETIN Bulgaria, CETIN Serbia, and the Technical University of Sofia, with Yettel Bulgaria and Yettel Serbia as associate partners.

• CETIN Bulgaria is upgrading the existing optical network and constructing around 100 km of new high-speed fiber connectivity between Sofia and Kalotina.
• CETIN Serbia is extending the cross-border connection by integrating base stations along the Kalotina–Dimitrovgrad section into its high-speed network.
• The Technical University of Sofia will conduct independent measurements and analyses of both the upgraded and newly built routes, testing optical parameters and detecting any potential frequency disturbances relevant for future road safety applications.

Impact and Results

The 5G Balkans project will establish the foundation for advanced mobility and intelligent transport systems across the region. By improving fiber optic connectivity, it supports the broader digital transformation of transportation, enhances cross-border collaboration, and contributes to safer, smarter, and more sustainable travel throughout Southeast Europe.