The Siege of Sevastopol, part 1: Beyond Barbarossa, episode 15

How the home port of the Red Navy's Black Sea Fleet earned the title, "Hero City of the USSR." 

Map 1: Crimea

 Source: Nations Online 

Map 2: The Siege of Sevastopol 

Source: Warfare History Network 

Other sources: 

Clayton Donnell, The Defence of Sevastopol, 1941–1942: The Soviet Perspective. Barnsley, UK: Pen & Sword Books Ltd., 2016.

David Glantz, Operation Barbarossa: Hitler's Invasion of Russia 1941. Stroud, Gloucestershire, UK: The History Press, 2011.

David Stahel, Operation Barbarossa and Germany's Defeat in the East.  Cambridge, UK: Cambridge University Press, 2010.

Siege of Sevastopol (1941–1942), Wikipedia.