My trip last August was for 11 days.
In the past I usually wore high priced sport sandels with no socks and was fine. However, this trip after two days I couldn't walk.
I had nothing to lose so I bought a pair of crocs in the gift shop.
No joke, it was instant relief. I wore them the rest of the trip with no socks and was able to walk everywhere and stay on my feet without hurting at the end of the day like they normally would have.
Crocs literally saved my vacation and I am going again this August for 11 days and they will be the only shoes I will bring.