Xincheng Brick Mural Paintings of Wei and Jin Dynasty's Tombs, located in Jiayuguan, Gansu, are hailed as the "world's largest underground art gallery". Dating from the Wei and Jin Dynasties (220–419 AD), this complex has over 1,400 brick tombs, with 700+ well-preserved painted bricks unearthed.

Each brick depicts a vivid scene: farming, hunting, feasting, and daily labor, reflecting the era's social life, economy, and folk customs. The art features simple, bold ink outlines filled with ochre and red pigments, boasting a rustic, lively style. A standout piece is the "Postal Messenger," an iconic symbol of China Post. These murals, earlier than Dunhuang Grottoes art, are priceless treasures for studying medieval Chinese painting and society。