Smokers are everywhere.
Easily the biggest downer about going almost anywhere in Belgrade, cigarette smoke and smokers are everywhere. They’re rarely blocking sidewalks, since smoking is explicitly allowed in many restaurants / indoor businesses. Some have a ‘non-smoking’ section, but there are rarely any barriers or air filters.
Look for the black ‘smoking allowed’ sign or the white ‘no smoking allowed’ sign near the entrance or on the door — and don’t be surprised if you see both signs!