Tarragona vs. Girona

We're trying to decide which one to pick. We can only pick one in addition to Barcelona and Montserrat. I understand Girona is known for it's Jewish history but we're not really Jewish, we're raised Catholic. But religion aside, we are more interested in seeing historical sites and ancient ruins.

I'm leaning toward Girona but Tarragona looks interesting too. I just noticed that there's not a lot of tour company that offers Tarragona tour. We are doing a private tour and so I'm looking to get our money's worth. Any help or suggestions will be greatly appreciated. Thank you.

I would choose Girona. it has a lovely old city and an interesting cathedral. The surrounding countryside is also prettier than around Tarragona. Maybe you could include one of the Dali sites if you are interested in art as they are not far from Girona?

Girona is a lovely medieval city, very interesting, UNESCO World Heritage and all. We walked through the old Jewish district, and saw the cathedral--you can also walk up on the medieval walls if you're into it. If you're doing a private tour, you might want to add Figueres to your day and see the Dali Museum.