From a piece in The Awl...
Do you consider this all art? Or is there another word you'd use?
Other people have used the phrase "GPS art," but I've started calling it "Virtual Geoglyphic Adventure." It's “virtual” since there's nothing left behind. “Geoglyphic” because—you know what geoglyphs are, like the Nazca Lines. So, it's like a virtual geoglyph. And then it’s “adventure” because when I'm doing these things I really don't know what I'm gonna see out there. Baltimore is happening no matter what.
Batter Up 10.39 Miles => 1 Hour 24 Minutes 54 Seconds
Fascinating. There's much more at the link, including how Wally actually does the drawings, how he got into it, and a few more geoglyphs.