Answer
Daming Palace was not a significant site during Xuanzong's reign because it was partially destroyed by a fire in 857 and never fully restored. Although Emperor Xuanzong considered rebuilding it, other palaces like Xingqing, Cuiwei, and Qujiang became the preferred imperial residences during his reign. These three imperial residences were within the walls of the capital city, Chang'an, while the Daming Palace was to the north of Chang'an.