What are the best things to do with 2.5 days in Palermo?

Lots to see and do in Palermo. Go to the outdoor street markets - maybe take a street food walking tour. Several have been recommended here on the forum by others. See a puppet show . Check to see if there are any opera performances at the Teatro Massimo or concerts at Teatro Politeama. Visit the archaeology museum Antonio Salinas. City is very walkable. See the Quattro Canti and nearby piazza Pretoria and Church of San Cataldo. Lots of churches everywhere - for Baroque opulence try Chiesa del Gesu. If you are in to seeing churches and religious experiences you might consider a visit to Mt. Pellegrino and the cave shrine of Sta. Rosalia - patron saint of Palermo. If you like weird unusual stuff there are the Capuchin crypts. If your tour does not include visits to Segesta or Cefalù you could do a daytrip to one of then. Cefalù is an easy train or bus ride. Segesta is not so easy to get to by bus but there are daytrip tours or use a private driver to get out there. Get a good guidebook to see what appeals to you.

It sounds from your description like your tour takes you to the Cathedral in Palermo but perhaps not inside the Cathedral at Monreale. The latter is the more impressive one--definitely one of the top sights on the island. It's a do-not-miss stop.

I agree with acraven and want to add that the Monreale cloisters were beautiful and to me worth paying the extra fee to see.

Thank you so much for your recommendations!

We did the Streaty Food Tour, and the NoMafia Tour, both at night. We loved them both. The guide for the food tour was a local residence and as we walked by his building, one of his senior neighbors lowered her basket and told him to buy something for her! He got us to try food we never would have tried on our own. The mafia tour talked mostly about the judges that were involved in stopping the mafia as well as a group that put a stop to merchants having to pay protection money.

Palermo is an absolute pleasure to just wander and explore. I definitely recommend hitting a market or two, or all three! They have vastly different personalities to them which is pretty interesting in itself. I though the Oratorio di San Lorenzo was amazing. We may be taking about the same church but Chiesa di Santa Caterina d'Alessandria on Piazza Bellini is jaw-dropping. A tour of Teatro Massimo is kind of the other big tourist stop. It’s cool, but if you’re enjoying yourself elsewhere I wouldn’t work real hard to see it.