The Moriah Museum of Dwarven Artistry

From the introduction:

Deep beneath the jagged peak of the mountain only known as The Ice Titan lies the lost dwarven city of Moriah. It was at one time the center of dwarven mining industry and gem trade. Then, at the very peak of the city’s influence, the mountain suddenly exploded in liquid fire. Magma and earthquakes destroyed most of the city in the span of a few hours, and those that escaped were lucky to escape with only their lives. The Ice Titan has long since gone dormant, and the memory of Moriah exists only in the most obscure tomes of history. Though the eruption destroyed large swaths of the underground city, there still exist areas that remain largely untouched since the day the mountain exploded.