### Iran Turns to Caspian Sea as Southern Trade Routes Come Under Pressure
Iran is increasingly turning toward the Caspian Sea and northern land corridors as alternatives to its traditional southern trade routes, amid severe disruption to maritime traffic through the country's Gulf ports.
The shift is placing greater importance on ports such as Bandar-e Anzali and Amirabad, as well as Russia's Caspian ports at Astrakhan and Makhachkala. However, the northern network has significantly less capacity than Iran's main southern gateways and faces its own logistical constraints.
According to recent reporting by Al Jazeera, Iranian officials say the share of essential goods moving through the country's northern ports has risen from about 18 percent before the conflict to around 30 percent currently. Gilan Governor Hadi Haghshenas also said container arrivals at Caspian ports increased by 50 percent year-on-year during the five Iranian calendar months ending August 22.
The increase reflects an effort to redirect cargo away from Iran's southern coastline. Before the current conflict, the overwhelming majority of the country's maritime trade was handled through southern ports, while the Caspian ports accounted for a much smaller share.
### Northern Routes Face Capacity Limits
The Caspian Sea can provide Iran with an alternative maritime connection to Russia and the wider Eurasian transport network, but it cannot immediately replace the capacity of the country's major southern ports.
Iran's Ports and Maritime Organization has said the country's northern ports represent only about 30 million tonnes of its approximately 300 million tonnes of total nominal port capacity. Iranian shipping officials have also warned that falling Caspian Sea water levels are restricting vessel sizes.
According to Al Jazeera, vessels that previously could carry up to about 6,000 tonnes at some northern Iranian ports are now limited to approximately 4,000 tonnes because of declining water levels.
The disparity in vessel capacity means that cargo that could potentially move aboard a single large ocean-going ship through Iran's southern ports may require a much larger number of smaller vessels on the Caspian.
Russia's Astrakhan port presents another operational challenge because it sits within the Volga River delta, requiring shallow-draft vessels to navigate the river system before reaching the Caspian Sea.
### Land Borders Under Pressure
Iran's northern strategy also extends to road and rail connections with neighboring countries.
At the Norduz crossing between Iran and Armenia, as many as 1,800 trucks have reportedly been waiting at times, while other border crossings have experienced delays of 10 to 15 days. Researchers cited by Al Jazeera say the congestion is not solely the result of diverted freight, with limited terminal capacity, customs procedures, road infrastructure and construction also contributing.
The eastern rail network provides another potential route toward Turkmenistan, Kazakhstan and China. Iran is also seeking to strengthen its connection with Russia through the International North-South Transport Corridor, including the long-delayed Rasht-Astara railway project.
However, the northern rail network has also been exposed to the risks created by the conflict.
On July 9, a railway bridge at Aq Tekeh Khan in Iran's Golestan Province was damaged. Iranian authorities and media attributed the strike to a U.S. cruise missile attack, while Washington has not publicly confirmed the strike. The bridge forms part of the Gorgan-Incheh Borun railway connecting Iran with Turkmenistan and the wider Central Asian network.
Iranian railway authorities subsequently reported that service on parts of the affected network had been restored rapidly following the damage.
### Caspian Shipping Becomes More Important
The growing pressure on southern routes is making the Caspian Sea an increasingly important component of Iran-Russia trade.
Cargo moving north can travel from Iranian ports such as Bandar-e Anzali and Amirabad across the Caspian to Russian ports including Astrakhan and Makhachkala, where it can connect with Russia's river, rail and road networks.
The International North-South Transport Corridor provides a broader framework for this trade, linking Russia with Iran and onward to South Asia and other Asian markets. The route has already been used for Russian exports to Iran, including grain, machinery and industrial products.
The current increase in Caspian traffic nevertheless highlights a basic limitation: Iran's northern infrastructure can absorb only part of the cargo that normally moves through its southern gateways.
For shipping operators, the result is a rapidly changing regional logistics map in which the Caspian Sea, Russian ports and Central Asian rail connections are becoming more strategically important. Whether these routes can handle a sustained and much larger diversion of Iranian trade will depend on vessel availability, port capacity, water depths, border efficiency and the security of the rail corridors.
For now, the Caspian is becoming an increasingly important alternative—but not a full substitute—for Iran's traditional southern maritime trade network.