Last updated: 4 November 2026

Bosphorus shipping is the flow of about 40,000 merchant ships a year through a 31 km strait that runs straight through the middle of Istanbul. It is the only sea link between the Black Sea and the Mediterranean. On a ship you pass palaces, mosques and waterfront mansions close enough to read the shop signs. There is no scheduled freighter-passenger service built around the strait itself, but some freighter and cruise voyages to Black Sea ports transit it.

What is the Bosphorus?

The Bosphorus (Turkish: İstanbul Boğazı) splits Istanbul between Europe and Asia. It links the Black Sea in the north to the Sea of Marmara in the south. With the Dardanelles further west, it forms the Turkish Straits. The channel is about 31 km long and narrows to around 700 m near the Rumeli Hisarı fortress. Three suspension bridges and a road tunnel cross it, along with a railway tunnel under the seabed.

It is one of the hardest busy waterways to navigate. The route has sharp bends, strong surface currents running south from the Black Sea, and dozens of ferries crossing at right angles. In April 2026 the Turkish-flagged container ship KAPPA ran aground off Yeniköy after a reported steering failure. Traffic was suspended in both directions until tugs refloated her the next morning. No one was hurt.

How busy is Bosphorus shipping?

Official figures from Turkey’s Directorate General of Maritime Affairs, reported in the press, show traffic is high but drifting slightly lower.

Across both straits in 2025, general cargo ships led with 28,594 transits, followed by 15,559 bulk carriers and 10,659 container ships. Pilotage was provided to 48,579 vessels.

Watch: a boat trip along the Bosphorus

The rules: Montreux Convention, fees and pilots

The Montreux Convention of 1936 governs the Turkish Straits. In peacetime, merchant ships of any flag have freedom of passage. Warships face limits on size, numbers and time in the Black Sea. In February 2022, after Russia’s full-scale invasion of Ukraine, Turkey applied the convention to close the straits to warships of the warring parties.

Ships that transit without calling at a Turkish port pay fees for lighthouses, health checks and rescue services. These are set in gold francs and converted to dollars. From 1 July 2026 Turkey raised the benchmark to $6.70, up from $5.83. Press reports estimated that a 10,000 net-ton vessel would pay about $25,000 in transit fees. Before 2022 the same ship paid about $3,240.

Under Montreux, pilotage for transiting ships is not compulsory, but Turkey strongly recommends it and most large ships take a pilot. Turkish traffic rules also allow very large vessels and those carrying dangerous cargo to be held for one-way or daylight passage.

The Black Sea, grain and war

The Bosphorus is the only sea exit for Ukraine, Romania and Bulgaria’s Black Sea ports, and for Russia’s southern ports. Grain, oil and steel all pass through it. From July 2022 to July 2023 the UN- and Turkey-brokered Black Sea Grain Initiative ran inspections of grain ships in Istanbul. War risk still affects insurance and routing in the northern Black Sea. For passengers, this is the main reason Black Sea voyages are rarer than before 2022.

Bosphorus ferries and tourist cruises

You do not need a freighter to see Bosphorus shipping up close. Istanbul’s public ferry operator, Şehir Hatları, runs two tourist routes from Eminönü:

• Long Bosphorus Tour: about six hours, calling at Beşiktaş, Üsküdar, Kanlıca, Sarıyer and Rumeli Kavağı, with around three hours ashore at Anadolu Kavağı near the Black Sea mouth.
• Short Bosphorus Tour: about two hours, turning around near İstinye.

Regular commuter ferries are cheaper still. An adult Eminönü–Üsküdar crossing was listed at 53.20 TL in 2026 (indicative). Private operators also run sunset and dinner cruises. Prices change often, so check with the operator.

Watch: why Turkey planned Canal Istanbul

Canal Istanbul: still on hold

Canal Istanbul (Kanal İstanbul) is a planned 45 km waterway west of the city to take ships away from the Bosphorus. President Erdoğan laid its foundation in 2021. In May 2025 the transport minister said it was “not on our agenda today”, but would go ahead once financing was found. Ministers have described it as a $15–20 billion project. We found no report of main construction starting by late 2026. For now, every ship still uses the Bosphorus.

Freighter and cruise routes through the strait

Ships that pass through the Bosphorus include container feeders, bulk carriers and tankers serving Black Sea ports such as Constanța in Romania. A few freighter lines that take passengers call in the eastern Mediterranean and occasionally the Black Sea. Berths are limited and itineraries change at short notice. Mainstream cruise lines still call at Istanbul, though few now continue into the Black Sea.

Tips

1. Sit on the right-hand side heading north from Eminönü for the European shore and its palaces.
2. Go early in the day on the long ferry tour; seats fill fast in summer.
3. Use an Istanbulkart for regular ferries; it is cheaper than single tokens.
4. On a freighter, ask the officers when the pilot boards; transits can happen at night.
5. Bring a telephoto lens: large ships pass mansions and bridges at close range.
6. Track ships live with an AIS app to see what is coming round the bends.

Foire aux questions

Sources: Türkiye Today (2025 Turkish Straits transits; July 2026 fee change), BTA (first-half 2026 transits), Marine Insight (KAPPA grounding, April 2026), Reuters via Arab News and Daily Sabah (Canal Istanbul, May 2025), feribotseferleri.com.tr (Şehir Hatları tours, 2026), Montreux Convention 1936. See also our guides to the Kiel Canal, the Canal de Suez et cargo ship piracy. Checked November 2026.