The Dream Cave is not technically a place - it appears in Alex' mind only in The Enchantress Returns. She goes there in a dream after being blasted into the air by Ezmia, and meets her literary heroines there. They talk to her, giving her the courage to defeat her foe.
The cave is dark, but Alex has a lantern. She doesn't know where she is, but instantly feels safe.
- ↑ TLOS II, ch 27, p. 467