For mail pigeons probably all heard, I will not repeat. I can only say that in 1941 the ornithologists of the USSR really did a great job of introducing suitable breeds of pigeons into the Red Army for the delivery of mail.
After all, the USSR was truly a "people's war" and people of various professions and hobbies invested in it as they could. And these postal pigeons were used there, where otherwise the mail could not be delivered.
I will tell you more about the postal and pigeon service of the USSR the next time. By the end of the first year of the war, the USSR military mail delivered up to 70 million letters to the front monthly. This figure shows that we managed to establish an effective military mail system.
The postal service, by the way, during the war years was transferred to the round-the-clock mode of operation, its staffs were doubled. Postal trains and wagons (the efforts of the People's Commissariat of Communications Peresypkin) were given the status of strategic cargoes. Letters and parcels were delivered to the front in the first place, along with ammunition. Modern researchers even argue that in 1941-1945 postal items in the USSR were delivered rather than in our time. It is likely: after all, then these goods went as a letter.
Of course, if the postal echelons perished, or the military unit itself got surrounded or destroyed, the letters were not delivered.
For the delivery of mail, sometimes all conceivable and unimaginable ways were used. So in the besieged Sevastopol letters came on submarines.
And in Leningrad, they were first transported through Lake Ladoga, and after the breakthrough of the blockade in 1943 on a reclaimed narrow stretch of land through a secret thirty-three kilometer railway corridor.
