Gozeksky circle are called concentric ditches with a diameter of 75 meters and log circles with gates. Through them, on the days of the summer and winter solstices, the sun enters the circle. This gave rise to the theory that this Neolithic structure is the oldest observatory in the world. Presumably it was built in 4900 BC. e. It seems that the creators of the ancient «celestial calendar» had a good knowledge of astronomy. It is noteworthy that there are similar prehistoric structures not only near Gosek, but also in other places in Germany, as well as in Austria and Croatia.