In the foothills of the Rhodope Mountains in Bulgaria, archaeologists have discovered three massive "bronze-inscribed" gongs. The artifacts, which date to the 8th century BCE, feature intricate celestial maps and inscriptions referring to the 'Festival of the Rising Sun,' a major event in the Thracian calendar that marked the triumph of light over darkness.
The gongs were positioned within a stone sanctuary designed to catch the first light of the vernal equinox, suggesting they were used as both astronomical markers and ritual instruments. This find offers a rare glimpse into the sonic landscape of Thracian religious life and the precision with which they tracked seasonal shifts. Researchers believe the gongs were struck to signal the start of multi-day mountain-top vigils involving dance and choral performances dedicated to the solar deity.