It is difficult to explain Belgrade in one sentence and get the scope of it in one day.
However, Walking Belgrade tours are genuinely crafted and well-thought-out. You will not only be able to tick off some of the must-see landmarks, but will be given a context to the sight and opportunity to learn of history, art and culture. Almost like a true insider. I particularly like small groups concept, which gives one enough time to stop, observe, process and share the experience with others.
Check out the blog on their website too.