Blisters. Strange thing about blisters. For the first few years of walking I used to pamper my feet, use mole skin, use surgical spirit, powder, creams, adjust my boots, everything you can think of...and I still got blisters...toes, heels, underneath.
Now I never seem to get them, no matter what I put on my feet or how my shoes fit.
Mind you...now the soles and sides of my feet are hard and shiny, with skin like armor plate. When I touch them I think that there is plastic sheeting stuck to them...but it is just the way the skin has worn.
Must be how postman's feet become........?