I was just wondering how long you call a good walk?

I take Chloe on two sometimes three 20 minute walks a day which suits as both. I don't think her little legs would carry on much further as I know she starts to look for a pick up.

Also I find she isn't that keen If I vary where we walk. Which is a shame as we have some beautiful walks where we live along the coast and I get bored doing the same route but when I try somewhere different for a change she can be quite stubborn and refuse to move on.
Do any of you come across this too?