Great Rift

The Great Rift was the traditional home of Faerûn's gold dwarves, though there was also a human city nearby, called Khôltar, until the Spellplague of 1385 DR. The country of 1,300,000 dwarves, gnomes, halflings, and humans was ruled by a monarchy from the capital of Underhome.

Collapse
When the Spellplague hit in 1385 DR, the western half of the Great Rift collapsed into the Underdark, forming an enormous canyon called the Underchasm. What remained of the Great Rift became known as East Rift. Underhome was destroyed in the cataclysm and the capital was moved to Eartheart.

Specific prestige classes

 * Great Rift Deep Defender Crypt (image)
 * Great Rift Skyguard (image)