Peter Jackson's crew made a great work portraying the Mines of Moria in their movies. If you want to see something eerie similar in real life, you can visit one of the original 12 Unesco World Heritage Sites, namely the Wieliczka salt mine near Krakow, Poland »
The trick is to think backward. Normally you paint shadows in the recesses of a model and then highlights on the edges emphasising how the external light plays on the shape. Fire has a light of its own and so the roles are reversed and the deeper you go, the lighter it will be. »