Which physical feature made it most difficult for traders to travel the western silk road?

“the battle of stalingrad is not a turning point necessarily in strategic terms, because a lot more has to be done before the soviets can be certain of defeating germany,” says renowned world war ii historian richard overy. the germans had fought nearly a thousand miles across the soviet union to get to stalingrad.

originally he was supposed to be dead but they wanted to continue the series so they brought him back to life.