What is the meaning of the underlined part please?
A: what do you miss most about Stockholm?
B: this may be looking back, but everything is within walking distance.
I think probably the speaker means that when they lived in Stockholm, they didn't appreciate the fact that everything is within walking distance. However, now that they don't live there, they can look back and realise that the fact that everything was within walking distance was a good thing, and is the thing that they miss.