My advise is to go with a shoe that has a thick rubber sole. The more rubber the better to separate your foot from the concrete. I am US born but live in Europe and developed serious foot problems when I wore Teva's. People have given you good advice about test driving your shoes. Shoes that feel comfortable when walking around the grocery store will not cut it. Practice walking a mile on cement everyday in the shoes you plan to wear. I would go for the shoes that look like tennis shoes but aren't tennis shoes. You will see many of them on the feet of travelers. After one day of walking on concrete, you will not care if your shoes are fashionable. Bring bandaids. Very important. Bring Dr. Scholl cushy inserts. Enjoy your trip.

If you will be walking 5-10 miles a day, which is very easy to do in Europe, I'd really suggest trying that at home with those shoes first. Also, consider having two pairs of different comfortable shoes - you might be glad for the opportunity to switch between them.

I was in Paris for a week this spring, and the entire time, I wore brand-new Josef Seibel walking shoes (the style is "Taylor"). I literally bought these 2 days before my trip and was so glad that I did. They required NO breaking-in period. They were a fairly clunky style, but when paired with stylish boot-cut jeans, they looked OK. Zappos sells them here http://www.zappos.com/n/p/dp/989812/c/10443.html

What surprised me most was the pace at which people walk in Paris was incredible -- and with so many women teetering on high heels literally ran up and down Metro steps, I felt pressed to keep pace. With my Josef Seibels t least my feet weren't killing me at the end of the day.

I walked so much in Paris on that trip that even with eating to my heart's content, I lost four pounds from all the extreme walking I did!

On the rare occasions that I did succomb to fashion and wear some far-less-cushiony boots, my feet were dying by the middle of the afternoon. I saved my real shoes for nice dinners where I'd take a taxi to the restaurant, or a quick Metro ride.

Hope this is helpful.

Jil Sander does fantastic trainers, but you might find their soles a little too thin for serious walking.

Tod's do quite smart leather trainers which have heavy soles with faux nubs on reflecting the heritage of the mainline ranges.

Your best bet is probably Prada Sport trainers as they're reasonably priced (160-200GBP) and have heavy rubber soles and hard wearing leather/nylon uppers.

m_kingdom2, are you sure there is quite enough oxygen at that altitude?

my pradas are not very comfortable on my foot. I wasted money. You must find a brand that suits you and stick to it.
Our feet all differ some shoes are narrower. Born has been my choice for casual and for dress I like Christian Louboatin.

It depends on what you feel is comfortable, however, Prada's trainers are well padded and part lined in suede so feel like butter on your feet.

As for heels ever being truly comfortable, it's an impossibility, but elegance and style should be your priority.

I agree with Betty070...Arche can't be beat! Walked from Notre Dam to the Eiffel Tower and halfway back with no problems