Soviet Red Army Stops Nazi Advance In Caucasus

The transcript describes the underestimated power of Russian air forces by the Nazis, leading to significant damage to German rail lines and air transport. On land, Russian forces advance along a 2000-mile front, recapturing villages. The retreating Germans, facing fuel shortages, burn their planes on the ground.

What geographical feature is mentioned as part of the battlefield?

How did the retreating Germans affect their own resources?