August–September 1941
The land routes close
Army Group North reaches the Leningrad approaches while German forces take Shlisselburg on September 8, severing the last land connection east of the city. Finnish forces advance on the Karelian Isthmus and then hold north of Leningrad; the encirclement is not a uniform ring of identical armies.
WHAT TO NOTICEThe city is isolated by interacting German, Finnish, and geographic barriers, with the decisive land closure at Shlisselburg.