Kulthöhle Zillis, Archaeological cave in Zillis-Reischen, Switzerland

Kulthöhle Zillis is a cave formed in a band of conglomerate rock at 940 metres above sea level, about 15 metres wide and 7 metres deep, above a terrace over the Hinterrhein. Remains of a mortar wall stand at the entrance line. The cave lies just 400 metres from the church of St. Martin.

Children playing in the cave in summer 1990 brought bones to pastor Huldrych Blanke, leading to excavations in 1991 under Jürg Rageth and Gian Gaudenz. These revealed a late Roman cult site used mainly from 260 to 500 AD, with fire altars and about 440 bronze coins scattered throughout. A La Tène burial from the 4th century BC and early medieval graves were also found.

The cave served as a place for religious offerings and ritual practices over many centuries. Visitors can imagine how people left coins, beads, and decorated vessels here to express their wishes or beliefs.

The cave lies at 940 m at the southern edge of Zillis, about 400 m from the St. Martin church, on a rock band above a terrace over the Hinterrhein. It is publicly accessible and needs no climb; the entrance is low, so watch your head. Above it stand the Hasenstein castle site.

Seven human burials were found nearby, showing how the sacred site transformed over time from a place of offerings into a cemetery. This is a rare example of a location that completely changed its purpose while remaining sacred.