A demi-plane to be precise. I can create a large tower of my own design, staffed by spectral fey servants, and as long as I have the components and enough energy for a powerful spell, I can set it up anywhere - the side of a cliff, a wardrobe.

In my tower, we have our own library and dining hall, staffed by kitty cat servants who cook any dishes you could want, and everyone has their own bedrooms.