Croatia plans 14 km tunnel for Rijeka rail

Croatia wants its main port, Rijeka, to compete with Koper and Trieste for cargo heading into Central Europe. The bottleneck is not at the docks. It is the railway climbing through the mountains behind them. HŽ Infrastruktura, the state rail manager, has received two offers for technical advisers on a planned "lowland" Zagreb-Rijeka railway: a double-track, electrified line that would cut roughly 56 km from the existing route and drive a 14 km tunnel through the Velika Kapela range (Index, Croatia Week). This is not a construction contract. It is the step before: hiring advisers to design the procurement.

Why 56 Km Changes the Freight Maths

A container ship can dock at any of the three northern Adriatic ports. The competition starts the moment cargo touches land. If freight crawls through a single-track mountain railway where trains can only pass in one direction, if steep gradients limit how much a train can carry, the port's coastal position counts for nothing. Shippers choose the route where a container reaches Budapest, Vienna, or Prague cheaply and on time.

The existing Zagreb-Rijeka line imposes exactly those penalties. The planned lowland route would let trains run 740-750 metres long on gentler grades with double track (TEN-T Regulation (EU) 2024/1679). Why does length matter? A longer train carries more containers per driver, per locomotive, per timetable slot. Double track means trains moving in both directions at once, which multiplies the number of usable paths per day. The result is heavier loads, lower traction costs, and more reliable schedules.

TEN-T, the EU's core transport network, rewards projects that remove cross-border bottlenecks. The Connecting Europe Facility (CEF), the bloc's transport infrastructure fund, finances exactly these corridor links (CEF Transport). Croatia's strongest pitch is that the railway removes a European freight bottleneck, not just a national one.

The Rivals Have Their Own Problems

Rijeka is not racing alone, but each competitor also lives or dies by inland rail.

Koper, Slovenia's only port, is investing over €230 million to expand container capacity from roughly 950,000 TEU (a TEU is one 20-foot container, the standard counting unit) to 1.3 million TEU (Regional Obala). But Koper's long-delayed Divača-Koper second track remains its weak link, with Slovenian reporting alleging construction projects are being overpaid by at least 30% (Info360).

Trieste has strong customs positioning. Italy's transport minister Matteo Salvini has pushed a Trieste-Belgrade railway to extend the port's reach into the Balkans (Trieste All News). Yet a recent closure at the Tarvisio rail crossing disrupted around 150 trains a week, showing how fast a single chokepoint can cut a port off from its customers (ilnordest.it).

The landlocked countries in between want options, not loyalty. ÖBB Rail Cargo Group has expanded its terminal at Přerov in Czechia and plans rail links to both Koper and Rijeka (ÖBB/RCG). Hungary frames Adriatic access as a strategic logistics question across both energy and container cargo (G7/Telex). For these countries, the winner is whichever port offers the cheapest, most reliable end-to-end corridor.

Who Pays, Who Gains, What's Unproven

If Croatia delivers, port operators and freight companies gain first. Inland logistics hubs in Zagreb and Central Europe gain next. Importers and exporters gain route choice and, potentially, lower costs.

Taxpayers, Croatian and European, carry the downside. EU corridor funds committed on optimistic traffic forecasts are money that cannot go elsewhere. No verified cost-benefit analysis, construction timetable, or traffic forecast has surfaced publicly. A Croatian maritime analysis frames Rijeka as the port with the largest growth potential, if it fixes inland rail (Pomorac.hr).

Croatia has moved the paperwork forward for a project that makes economic sense. But Rijeka's advantage will not come from being nearer on a map. It will come only if the new railway cuts the cost and uncertainty of moving cargo inland, and only if shippers choose those trains over the alternatives from Koper and Trieste. Until trains actually run longer, heavier, and more reliably into Central Europe, Rijeka is buying a ticket to a race whose outcome depends on execution.