Bought them in Italia. I've never worn Birkenstock's before. I wore them all day for the first day and my feet hurt. I have huge problems getting proper shoes. I'm used to getting shoes that don't fit comfortably.  I figured I did it again. They cost less in Europe. In Italia about 95 US.  However, by the third day it all got better, much better. About 20 hours and 15 miles of walking. I wear custom orthotics  but did not with these. Usually, after a few days without, my feet hurt badly. Never happened in a month of walking approximately 10 miles a day on all kinds of terrain in Italia . Up hills, cobblestone streets, beach/sand. I wore them barefoot . More comfortable than  actually being barefoot.  SOLD.