The Valley of Royalty was an ancient valley on Duro where the Duros buried many of their most celebrated rulers, including Rana Mas Trehalt. There were many secret catacombs and caves in the Valley, hiding a wealth of both historical information and valuables. The Valley was flooded with toxic waste when the Tiercam Dam broke, almost killing several Duros archaeologists. The valley was listed as one of the Twenty Wonders of the Galaxy by the historian Vicendi in 10,000 BBY. It was abandoned by 4000 BBY.