mossy grotto, Hidden Gardens and Grottoes of Dewstow (3) by -terry-, via Flickr
Hidden gardens of Spitalfields Even the most urban areas could achieve this.
Hidden Gardens via Beacon Hill Garden Club
18 Secret Ideas To Plan Your Hidden Garden! More
A secret garden reading spot --> jaja, dit is het!
Romantic Fairytale Garden | Fine Gardening
Cozy shade garden. Lovely place to get away. The link didn't take me to this image but there's other nice scenery there...
A garden doesn't have to be large...A small, lush, enclosed garden area
Tim Wilmot's backyard tropical garden | Bristol, UK