I am having a little trouble trying to figure out how to answer your question.
Do you have a car, or will you be using public transportation?
I would say that almost any permutation of your answer would yield the sentiments that it would be more than a day trip.
If you are going to be in Madrid, then conceivably you could take the fast train (AVE) to Sevilla or Córdoba, and make that a day trip.
Give us more info, and I am sure you will get specific comments...