I am a sucker for catacombs so that is what drew me here. Having said that, there were many other interesting things to see. Some fabulous old paintings, including an absolutely massive one. An incredible library with ancient volumes. Our tour guide spoke virtually no English, which was pretty limiting but we muddled through. Surprisingly interesting all in all. Wouldn’t make the top of my list but worth a side trip if you have the time. Kind of hard to find, by the way. Google maps shows it right off the big plaza. It is not. It is off the San Francisco Square about 2 blocks away. Had to roam around a bit to find it.