Twigitecture - Building Human Nests - NYTimes.com
Backyard Design: DIY Outdoor Sound Wall/Music Station | FUN AT HOME WITH KIDS
I like the simplicity of this wooden house.
wooden hobbit play house
hobbit play house
hobbit house in the hill
bottle glass in a play house wall - omg, rainbows + hobbit house = magic.
several cute hobbit house examples
Love this tree window (door?)
fairy house play house
Tons of natural wood play space ideas on this site!
Fun club house with swings, slide, climbing structure, and more.
Slideshow with 14 different tree/play house ideas.
outdoor mud pie kitchen for kids
huge Tree house with slide, rock wall, swing, etc
Tree House with stairs
tree house with boards on the ground floor, around a tree
tree house with rock climbing wall, slide and deck
This is pretty much the coolest tree house I've ever seen!
More ideas for stumps, a barrel, and a tire swing
Outdoor roadway using PVC pipe for a tunnel and bricks for the road
Use a shed for a playhouse