In this report the author views the original symbolic images disc-, crescentand half-moon-shaped with one-two ray-like lines, directed to one aside. These pictures have been carved on capes rock tips of the eastern coast of the Onega Lake (61º40′ n.l. & 36º e.l.) together with depictions of waterfowls, elks, ships, men ets., opened 160 years ago. This images had belonged to the population of Pit-Comb Ceramic Culture (the end of the 5-th the middle 3-rd millennium BC). The author analyses indicated figures in a complex manner, taken into consideration the graphical, cultural and chronological, natural and geographical, topographic and astronomical particular features. The main focus of the report is the interrelationship between the orientation function of the figures, peculiarities of their forms and azimuths meaning, calculated on the basis of the directions of rays-like parts of the signs. Total amount of the analyzed symbolic figures is 62. The results of the research is demonstrates the connection of the examined carvings with the azimuths of the moonrises and moonsets in all the visible phases on the days of equinoxes and solstices. Only eight figures can be belonging to solar symbols. Such situation may be connected with the existence of the lunar calendar. Taking into consideration the specific conditions of the Sanctuary location on the Onega Lake, peculiarities of the forms and semantic content symbolic figures, the author hypothesized that one-two radial lines, located on the solar and lunar signs, could depict the Sun and Moon paths on the lake surface and indirectly to indicate Sun and Moon risings and settings azimuths on the water horizon. The main body of the figures reflected form peculiarities of the observable heavenly body. There are the reasons to think that a lunar and a solar signs of a similar type have been the most ancient astrolabes. The majority of them had pointed to the directions to a place of the luminaries rising and setting on the horizon. Some figures marked a mutual position of the Sun and the Moon at the time of rising and setting in the astronomically significant days of year.