Archaeologists in Henan Province have uncovered a sophisticated network of winding stone canals dating back to the Western Han Dynasty, specifically designed for the 'Floating Cup' (Qu Shui Liu Zhu) ritual. This practice, a hallmark of the Shangsi Festival (Double Third Festival), involved floating wine cups down a stream; wherever the cup stopped, the person seated nearby would drink and compose poetry to ward off evil spirits.
Sediment analysis within the stone troughs revealed high concentrations of orchid and peach blossom pollen, suggesting the water was intentionally perfumed for the ceremony. This find represents the earliest physical evidence of the 'Spring Purification' festivals in China, showing that the elite of the Han era had moved beyond simple ritual washing to highly aestheticized, literati-led celebrations of the natural world and cultural heritage.