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Yes if you are an ATT subscriber

I have used an iPhone 3G and 3GS in rome on a number of trips. As soon as you arrive at Leonardo Da Vinci you will receive a series of text messages from the local providers soliciting your business. Chose any one - you can always change later.

Remember to subscribe to a foreign calling plan before departure and turn off roaming when you arrive. I generally activate roaming 3 times per day to check email etc. morning noon and just before dinner.

I hope this helps
 
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