Internationally using Location Services without having data charges. What settings should use on my iPhone 5?

I'm traveling to Europe and I want to use Location Services without having data charges. What settings should use on my iPhone 5? I want to be able to use Trip Advisor City Guides Application to tour around cities for free. I have a Verizon International Plan for my trip, but it is still pricey. I would like to keep my iPhone cell services on for incoming calls, but I want to prevent international data charges. Thanks for your help!