Best pair of sneakers for walking?

I will be walking long distance next summer... I'm going to Europe! 10-12 miles a day, and I barely walk a mile a day now. To say the least, I'm inactive. Not fat, but inactive. Anyway, I want to do this for myself and so I'll be prepared. What shoes are good for this? What brands? What specific shoes? Any good deals? also, are pumas any good?