The gyros I have eaten on many a drunken night here really remind me of the gyros I have eaten on many a drunken night in Chicago. And so does the seedy, butt-ugly atmosphere of this place. But if eating some of the best gyros ever in Chicago has taught me one thing, it's not to judge a gyro place by its cover. Parthenon Gyros is no dirtier than the kitchen located right next to the counter, in true big-city style.
The fries are usually cooked and seasoned very well, and they don't do a bad job with things like the spanakopita either. I love the tzatziki sauce; you get a good 50/50 mix of yogurt and mint in the aftertaste. Like every other topping, including the gyro meat, it is generously piled on top of the bread (another one of their most outstanding ingredients).
Parthenon is very fast-foody, but I don't know a good gyro place that isn't. So if you want to escape the dining room that looks like a bathroom, go to the rooftop tables. You can watch State Street go by while you eat one of the best gyros in Madison.
Oh, and they serve beer.