The original edition of "One Summer" from 1979 included two hand-drawn maps that I made of the Lents area as I remembered it from the late 40's, and as it appears in the story. This large map shows the general Lents area, including directions to Portland and Gresham. In the 1979 edition it appeared on a fold-out page. In the more current edition the map was printed on two pages.
Here's the legend indicating where key points of "One Summer" occur within that map.
I also drew a detailed map of Chris' neighborhood, "downtown" Lents. It shows the old Lents grade school, Rexall Drugs, the Oregonian branch, and other features of the landscape that appear in the story.