The more I think about it, the more I like the idea of Otherworlds as a focus for a setting. They let you keep the familiar reality of a low-fantasy world, but have your characters encounter magical, high-fantasy elements when need be. I'm hoping that both sides of the coin will benefit from the contrast of the other. But the idea of jumping into new realities is hardly a new one in fantasy. From Planescape to the more accessible 4e Cosmology D&D, the elephant-in-the-room for any fantasy RPG, has covered quite a bit of ground itself.
For my Adventurer's Setting I want something a little less defined. Something more Fairytale than Epic. I'm definitely thinking more akin to Wonderland, Oz, Neverland and Narnia than the Great Wheel. Places where adventures happen and rules of nature are broken, as well as a source for magic to leak into the natural world in small doses.
However, my experience of these sources is a little limited, as may be clear. My examples are exclusively from sources I remember from my childhood. What reminded me of this concept recently was reading about the Celtic Otherworld, and I'm familiar with many of the analogs in other culture's mythology. What I'm calling out for is recommendations for other sources of inspiration for fantastic places existing outside of our world.
Any suggestions for me?