Really exceptional, in all respects. The audio tour adds so much in-depth enjoyment to the visit of this ancient site. Yeah, Romans finally did fail and Rome did fall, but, wow, when they got things right, they got them RIGHT! When the Romans were using this, the water was as clear as any modern swimming pool...now, algae colors it green.
See everything if you can, make a wish at the pool, and be SURE to taste the actual water toward the end of the tour but only at the designated fountain! It will be a little brackish, but, hey, it might cure what ails ya.