It takes a long time to wear out a Birkenstock, a favorite sandal of Boomers (with or without socks). Here's a comparison of a new pair to an old pair worn daily
Birkenstock Arizona Stone Birkoflor | Hanigs Footwear
Arizona | Birkibuc | Mocca – Birkenstock Midtown
Birkenstock Limited Edition Arizona Big Buckle almond nubuck