Full explanation
In 2022–2023 grain flowed through the Danube to Romania's Constanța port (800 km downriver) and onward by sea. Limitations: (1) vessel draft — Handymax 35k t max, versus Panamax 80k t at Black Sea ports, making freight USD 8–15/t more expensive; (2) seasonality — low water levels in August–October limit loading; (3) transloading — one extra operation at Constanța (USD 60–120/t logistics). 2022–2023 advantages: (1) non-war zone, standard insurance; (2) rapidly mobilized infrastructure (Danube Shipping Company, 220+ barges, 35 tugs); (3) parallel alternative to the blocked Black Sea. From August 2023 (Black Sea Corridor opening), Danube port capacity became insufficient — throughput fell from 24 Mt (2023) to 13 Mt (2024). In 2026 Danube is mainly for bulk specials. Future: deepening the Danube's Bystre Canal to −7.3 m — accommodating Panamax.