Digital fantasay art picture

Design brief: realistic fantasy castle with impentrable walls set in mountainous woodlands. The walls and feel of the castle are of utter impregnability and should make it seem impenetrable. Inside the walls is a faint golden glow symbolising residual hope and love fiercely protected by the fortress surrounding them. The path to the fortress is narrow and difficult.
The design should be "physically possible" i.e respects our known laws of physics and construction.