nonfiction/knitting (advanced - mostly intarsia with some cabling/lace/embroidery; the book assumes that you already are familiar with the various stitches and techniques)

one size "fits an average adult size head" (approx. 19-22" or 48-56cm around)

The photos of the projects are really quite lovely, with the specific yarns picked out providing beautifully variegated effects. You may also substitute "other worsted weight (#4) yarn" but your results will vary.
Colorwork patterns frequently use 3-5 colors, so if you have a stash with lots of partial skeins in lots of colors, this book might be worth checking out; there are also some lovely patterns with one or two colors.

Some of the patterns definitely look better than others --the Sequoia trees look like trees whereas the Redwood trees look like alternating bars of brown and green; the Katmai bears look ok when worn in one picture, but laid flat on the cover, look like giant blobby gophers. Many concepts are unrecognizable in other contexts, but maybe you're ok with having a hat that looks weird but secretly you know that it replicates the stalagmite formations of the Carlsbad Caverns or the rippling landscape of White Sands, or the strange bubbling mudpot fumaroles at Lassen.

one thing I'd like to see: an index or table of contents with thumbnail pictures of the projects, so one doesn't need to keep flipping through the whole book to find their favorite patterns again. ( )