August 2021. Mariupol, Ukraine. The mariupol beach front and sea port in the background. The Kerch Strait is the only connection between the Black Sea and the Sea of Azov, and the only way to reach two important Ukrainian ports,Â MariupolÂ and Berdiansk. The route is vital for Mariupol's two large metallurgical plants. Russia has controlled the strait since annexing Crimea in 2014, which has made traffic significantly more difficult for Ukrainian ships. The consequences of Russian control have become particularly noticeable since the completion of the Crimean Bridge in May 2018. The FSB inspects all ships bound for Ukraine, sometimes taking days, which has aggravated the situation. The volume of freight has steadily declined since then. The war in Ukraine's Donbass region is also problematic for Ukraine's ports.