The sultan mainly resided in his palace, which is what you see in the photo.
It was built in the 15th Century. In bosnian its called "Stari Grad" which roughly translated means Old City.
It was an important building almost to the end of the Ottoman Empire rule.
Favorite thing: The bowsing at the internet point is cheaper (almost 50%) than Sarajevo and if it happens that you have a bit of time before the bus leaves (its a 10-15 min. walk upto the bus stop) you can brows here cheaper.