This rare sundial variant is known as a solstice sundial, consisting of two identical dials, one oriented to the east and the other to the west. Each dial has a shadow indicator, which stands perpendicular to the dial and is aligned with the North Star.

In the morning, the east side of the sundial is illuminated by the sun, while in the afternoon, the west side is lit. Depending on the position of the sun, the shadow caster projects a broad shadow band onto the hour-marked dials. The end of the shadow indicates the current time.

A unique feature of this sundial is its ability to simulate the seasonal positions of the sun, particularly the winter and summer solstices, as well as the equinoxes on March 21st and September 23rd. On June 21st, the day of the summer solstice, the tip of the shadow is at the lower edge of the dial. From there, the shadow gradually moves upward, reaching the middle on September 23rd, and continues its journey until December 21st, the day of the winter solstice, when it reaches the upper edge of the dial. Afterward, the shadow moves back in the opposite direction.

For the sundial to function accurately, it must be precisely aligned in a north-south direction and according to the local latitude. This sophisticated construction makes the sundial not only a reliable timekeeper but also a fascinating instrument that vividly illustrates the seasonal changes of the sun.