Dark Sun: The Scorched World of Athas
Only reached by a series of tunnels with psionically activated lifts, the city of New Giustenal exists beneath the ruins of the city-state of Giustenal. New Giustenal is a city of dray who are devoted to Dregoth as their god and protector. Morg and his allies are the only non-dray to have ever visited this city and lived.
The city was built in a giant cavern with 200 foot ceilings and a massive river of fresh water flowing through it. This river provides drinking water as well as some of the food consumed by the dray. The entire cavern is illuminated magically.
The entrance to the cavern is defended by massive gates made from a combination of stone and bones and protected by bone golems and dray templars. Beyond the gates lies a sprawling city, much like those above, but with a distinct draconic feel. Markets, taverns, temples to Dregoth and dwellings are surrounded by crop fields, an inverted forest and livestock.
The single most massive building in the city is the Dread Palace of Dregoth. This immense building is stark and oppressive, being decorated with the blackest obsidian and large bones.