5' x 2.5' x 2'
I visited a tiny library at Mt. Charleston in Nevada and loved it. I got home that evening and did some online research and found all sorts of crazy libraries, my favorites being ones that moved or were somehow portable.
In Mexico there's a mobile library that's a guy on a donkey, in Mongolia there's a dude on a yak with books attached to it, and in New York City there are people with libraries attached to a backpack. Pretty cool stuff. I might bring this to a park, festival or just an open spot in the woods.