The pé-de-moleque (urchin’s feet) cobblestones in Paraty's car-free colonial downtown area are taxing on your feet.
Avoid clogs with hard soles, high heels, and flimsy flats. Havaianas are OK – but only after you get the hang of walking on that ground.
Birkenstocks, which are open-toed but have thick soles, are an option. And of course, you can’t go wrong with a good pair of walking shoes.
If you’re going to be in Paraty on the first days of the new or full moon, keep in mind that part of the downtown area floods during the high tide (see photo by Daniel Menezes on Flickr). You'll have to avoid some streets altogether, especially near the pier. Still, consider packing some rain boots.