those are letter boxes..
Ha...yes i know all about them , i have one on the gate of my farm....But i noticed when i first came to Poland that houses and shops do not have the hole in the door with a letterbox , like for example in the UK...
I can remember going one night to a business place to drop off a letter , but could not find any letter box , thats when i noticed that no shop had such a letterbox....
Is there any cultural or political reason for this...?? have doors in Poland ever had a letterbox....??
Just wondered...???