Gallery Kalemegdan – Belgrade Fortress… Today Kalemegdan – Belgrade Fortress. It’s one place you most definitely shouldn’t miss while visiting Belgrade. Belgrade Fortress Kalemegdan… Today (click to enlarge): Karl HaudbourgI'm a Frenchman promoting Serbia in the world. I see myself as a Serb. Call me crazy. Call me insane. I am a pragmatic patriot. I love my country, Serbia.