site.btaUPDATED Day 2: In the Sea of Marmara

In the early hours of December 28, the Bulgarian military research/survey vessel (RSV) Sv. Sv. Kiril i Metodii passed from the Black Sea to the Sea of Marmara through the Bosphorus. At 8:30 a.m. local time, the vessel entered the approaches to the strait after receiving permission from the Turkish authorities. The vessel was escorted by a coastguard cutter as it crossed the 30 kilometres separating the European and Asian parts of Turkiye and Istanbul. 

At around 10:30 local time, the ship left the Bosphorus, heading for a berth for bunkering in Area B, where local authorities indicated a point with coordinates for the ship to anchor. Currently, a barge is waiting to refuel the ship by hooking up a hose to its system, navigator Capt. Hristo Hristov explained. 

The Bosphorus Strait is one of the most difficult to navigate in the world due to the heavy traffic of passing merchant ships, ferries and other small vessels, as well as its current, which reaches up to 6 knots, and the sudden changes in weather during the autumn-winter period. At its widest part it is about 3,700 metres and at its narrowest about 750 metres (between the Anadoluhisari and Rumelihisari fortresses). The depth of the Bosphorus varies between 36 and 124 metres.