Rock Sanctuary and Astronomical calendar in Kalugeritsa locality

Kalugeritsa rock sanctuary is located in valley of Smolska river, between the villages of Baylovo and Smolsko. It is a complex of four (most likely in the past there have been more) caves in travertine rock, which are situated in the lower parts (from 5 to 15 meters above the local erosion basis) of V-shaped section of the river valley. Caves are known among the local population as "Monkish" or "Monastery" caves.

The place is filled with energy and mystique. One theory is that this is an ancient facility (VI - V millennium B.C.), which was used as an Astronomical observatory for trace of moving of the visible celestial objects - the sun, the moon and the stars. In one of the caves the ancient inhabitants had cut down a special site from where they had ideal conditions for observation of the moon. There are traces of drilled square-shaped holes that connecting visually the caves with the sky and the observation site.

Inside the cave, archaeologists have uncovered about 240 images (carved or engraved into the rock), which at first glance resemble circles, but more detailed examination shows that these are different phases of the moon. Some of the signs are complete circles, and others are crescent-shaped, as the moon in the first or third quarter. Especially attractive are the prominent images of moons with low relief, which are relatively rare. It is believed they have recorded the lunar eclipses.

Successive changes of the moon disk are connected in groups of characters representing graphic registrations of certain intervals. Estimated records show periods related to the duration of the climatic seasons, vegetation cycles, the time between the different religious holidays and more.

Along with cut circles and symbols from the ancient times, here are found also crosses, indicating that probably the sanctuary was used during Christianity too.