Seven Kingdoms: Seowyn's Crossing
Zagundarga is a city in the Underdark. Originally founded by Drow, it was taken from them by Dwarves, who then lost it to the Duergar. The Duergar hold it to this day. Notable for its slave trade, it boasted an impressive temple to the Dark One. This temple was being corrupted by the cult of Ogremoch and the Elder Elemental Eye.
The Fire Wasps came to the city in search of Caius Wandersea and Leora Wandersea, and found they were being held for sacrifice at the temple. As a result of their actions, the temple became cleansed and converted to the worship of Shandalene where it is now a pilgrimage site for her worshippers.