"Orlovi skali" Thracian sanctuary is located in Ardino. "Orlovi skali" is a group of prominent volcanic rocks. They are located on a very steepy mountainous terrain at an altitude of about 760 m. They are located on a slope facing west. The height of the rocks reaches up to 25 m above the surrounding terrain.
Trapezoidal niches were carved in some inaccessible parts of the rocks. Ninety-seven of them have been preserved. Fifty-five are located on the west side. Five or six of them have either been weathered or may not have been completed at all. There are thirty-five on the south side and five on the north. On the east side, which is inaccessible, five or six have been weathered. No regularity has been complied with when they were arranged. The ancient stonecutter used any convenient location close to a single or group of holes in the soft volcanic rock. The shape of each one is trapezoidal while the sizes are quite different.
According to some authors, these niches belong to the Odrisses and date back to the first millennium BC. It was a place for cults. Containers for religious celebrations were placed in the rocky niches. Judging by the ceramic fragments found in the rocks, some archeologists believe that this shrine dates back to the 5th- 4th century BC. According to another hypothesis, the Thracian sanctuary dates back to the 1st millennium BC.
The inner sides of the many pieces of pottery found around Orlovi skali were burned. This fact supports the assumption that the Thracians poured fuel fluid in these bowls, lit and placed them in a special niche carved into the rock. This ordinance was performed on particularly solemn occasions, such as before and after completion of a war, etc. A further assumption is that these recesses were rock tombs- urns, where the Thracians put the ashes of the dead.
Despite the numerous suggestions regarding their use and date of origin, their secret message remains unrevealed. The ruins of an ancient Thracian fortress known as the "Kaleto" can be seen nearby (at the height before you reach the niches).