Dark Sun: The Scorched World of Athas
Vault of Darom Madar
Fabled treasure vault of the the long-dead Madar merchant house.
A possible location of this vault was revealed to Rhotan Vor of House Wavir while in Balic and the merchant launched an expedition to find the vault, lead by Kelvor. The expedition failed and it is believed that House Tsalaxa ultimately recovered the wealth.