At the base of Wulao Peak on Longquan Mountain, the grey tiles and orange walls of the Heilong Palace stand beside the Yin-Yang Twin Ponds. This site, known historically as the Lower Temple, originated in the Western Han Dynasty as the Heishui Shrine. Local conflicts destroyed a subsequent Yuan Dynasty temple here, leading to its reconstruction in 1394 as the Dragon God Shrine. In 1454, the Mu family, hereditary Dukes of Qian, funded a major rebuild, establishing the stone-lined boundaries of the ponds.

Human hands have left deep marks on these grounds. In 1690, Yun-Gui Governor Fan Chengxun carved his poetry directly into the stone tablets now embedded in the courtyard walls. In 1821, builders erected a reconstruction stele, leaving physical chisel marks on the stone. During the Qing Dynasty, official Lin Zexu composed a poetic couplet for the temple, which was restored on the columns in 2003. In July 1938, botanists Cai Xitao and Hu Xiansu hung the sign for the Yunnan Agricultural and Forestry Botanical Research Institute on the wooden entrance, transforming the ancient altars into laboratory benches.

The architecture follows a traditional courtyard layout with front and back courtyards. The main hall features a single-eave gable and hip roof spanning three bays. In the inner courtyard skywell, a sculptured black dragon rests in a decorative pond. Outside, the octagonal incense burner displays the Bagua trigrams and the Big Dipper constellation carved into its cold bronze and stone.

The physical environment provides immediate sensory contrasts. Cool, damp air rises from the deep, fifteen-meter-deep clear water basin, while the adjacent shallow, turbid basin remains warm and yellow. These two pools meet at the stone arches of Linyu Bridge, creating a sharp visual boundary where the waters touch without mixing. Golden thread fish swim through the clear depths, famously refusing to cross under the bridge into the muddy water.