Amongst my favourite free libraries are the book trees in Renfrew County where I grew up. Free Community Book Trees are currently located in Petawawa, Killaloe, Arnprior, Pembroke, Cobden, and in Bonnechere Ontario Provincial Park. In an area where forestry was a major industry, it is appropriate that already fallen trees from local forests are used. There’s a Facebook page with photos of the various book trees: https://www.facebook.com/TheBookTreeRC/.
The Bonnechere Park tree is unique as it is the first inside a provincial park. Made out of a massive 100-year-old white pine that fell during a wind storm two years ago, this Book Tree is crowned with an authentic Pointer Boat (http://www.thedailyobserver.ca/2014/08/24/book-tree-launched-at-bonnechere-park).
When visiting a community, why not hunt out the free libraries. The Globe and Mail even did a feature article on some free libraries in Toronto: http://www.theglobeandmail.com/news/toronto/free-libraries-in-toronto/article33979511/?click=sf_globe. There’s even an organization which can help you find these in your travels: https://littlefreelibrary.org/ourmap/.
If you would like to build a free library where you live, you can find advice here: https://littlefreelibrary.org/start/. And check out the tips from someone who has a free library: http://bookriot.com/2014/03/24/5-tips-running-little-free-library/.