The historic complex of Split is unusual in that it is entirely situated within the confines of the walls of Diocletian's Palace. When the Roman Empire crumbled, the locals huddled together for protection within the then-abandoned imperial residence, and they have remained there ever since. Due to this fact, Split has one of the strangest and coolest main entrances to an old town: through the main gate of an old palace entering up the stairs into a remarkable presidium. There's not much to see these days of Diocletian's living quarters, just some bare rooms with a few artifacts, but what is most striking is how certain structures of the palace, temples etc., have been coopted and transformed for the use of the current citizens. Split has a lovely little warren of streets to explore and some excellent cafes for sitting and watching the world go by. It's a great introduction to life on the Croatian coast and easily reachable by ferry from any number of Adriatic ports, including daily sailings from Ancona, Italy.