On Dayun Mountain, Yunshan Village, Maba Town, elevation 73.6 meters, 30 kilometers west of the county seat and 1 kilometer south of the ancient Dongyang City ruins. Adjacent to Qingdun and Xiaoyunshan Han noble tombs, it is the joint burial site of Liu Fei (1st Jiangdu King, son of Emperor Jing, half-brother of Emperor Wu) and his concubines. The nearly square mausoleum (500m per side) has walls on all four sides (only the east wall well-preserved, 2.3m high). It contains 3 main tombs, 13 accessory tombs, 2 chariot pits, 2 weapon pits, and 2 building foundations, yielding 10,000+ artifacts (bronzes, gold/silverware, jade). Main tombs lie south, accessory tombs north, chariot pits south, weapon pits north, and foundations centrally—strictly organized. The No.1 Tomb uses the highest-status huangchang ticou (cypress wood chamber) burial system, with a jade burial suit with gold threads and jade coffin—providing critical data for studying Western Han imperial tomb systems.