Your discussion of books about pretend play made me think of
Roxaboxen, another of those books that I'm surprised we haven't mentioned here. It's by Alice McLerran, wonderfully illustrated by Barbara Cooney (whom we also haven't mentioned enough).
McLerran writes about a group of children who create a whole city out of rocks, boxes, and various found objects in a vacant lot in Arizona.
Marion called it Roxaboxen. (She always knew the name of everything.) There across the road, it looked like any rocky hill -- nothing but sand and rocks, some old wooden boxes, cactus and greasewood and thorny ocotillo -- it was a special place.delightful-sounding park. It has a few benches and some signs and a lot of rocks to play with. Visitors are encouraged to donate rocks, knowing that they'll be added to the mix of stuff used by kids who play there.
So thinking about parks led me to Grant Park in Portland Oregon, in Ramona Quimby's neighborhood. We came upon it on our cross-country trip ten years ago, not far from where cousin Kate then lived. It's a nice comfy city park, with playing fields and trees, and in one corner of it are three statues and some very kid-friendly fountains:
Ramona Quimby, Ribsy, and Henry Huggins are right there, to be played with and splashed around. Ramona is wearing her boots and seems to be in the scene where she's a kindergartner stuck in the mud in Ramona the Pest. There's even a map of the neighborhood, marking places where events in the books happened.