Segesta is a beautiful example of life in the long departed Greek community in Sicily.
The temple here is in fairly good shape (for ruins anyway!) and the surrounding lands are amazing. We went in early spring and there were wildflowers in all colors everywhere! Another great thing to see here is the amphitheater which is very well preserved and offers great views of the surrounding countryside.
By the way, there is a bus that will take you up the hill to the amphitheater, but if you're feeling adventitious, skip the bus and walk it. Not only will you get amazing photos of the area, but you will also get to take in perspectives that few other do!