When I think of gnomes the iconic cover illustration of the iconic "Gnomes" book from the 1970s comes immediately to mind.
The cultural impact of the book was such that it shaped the way people imagined what a gnome might look like to the extent that the majority of contemporary garden gnome designs use it as a template.
On a personal level the image has a deeply resonant quality which has a portal-like ability to open pathways into memory and imagination.