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.