Kris Kelsay, the author, is a Mercer Island resident. She says:
Recently, I’ve been puzzled when my hard-core walking and running friends didn’t know about the trails and cut-thrus in their own backyard. Then I realized they have become much harder to find. There is no guide available and many of the path signs have disappeared or been hidden with strategically placed landscaping or a potted plant; and some have simply become inaccessible, period.
There’s also views of Rainier, sunken forests, and hidden trails but I’ll let you find those walks. Definitely a book worth getting.