One of my favorite places when I visited Sicily a few years ago was Salemi
in Trapani, a town about 1 1/2 hour outside of Palermo. (There's another Salemi near Catania; don't confuse them.) As it is in most of Sicily, history is everywhere you look. Over the centuries Salemi has been occupied by Greeks, Romans, Vandals, Goths, Arabs and Normans, to name only a few of the conquerers, and every one left traces of their presence which still stand today. There are plenty of castles, churches and museums to visit, and beautiful parks for hiking among ruins. If you spend any time there, a must-see is the splendidly preserved Doric temple and amphitheater nearby in Calatafimi
. The town of Salemi is large enough to have places to stay and many restaurants, while still being small enough to get around without difficulty. It's not a tourist town, so few people there speak English (which might be a problem if you don't speak any Italian at all) but in my experience, almost everyone was eager to welcome foreign tourists.