3400: Monuments in Netherlands, northern Germany, Sweden and Denmark. 2800: Highpoint of Danish Funnel-beaker culture in Denmark.3300: Construction of the German stone cist known as the Zuschen tomb. 2700: Start of the Old Kingdom Egyptian Pyramids in Ancient Egypt.
In the north, the megalithic tradition first appeared in Manchuria, notably in the basin of the Liao River, from where it spread into the Korean Peninsula.
Aside from their unique architectural designs, megalithic monuments were typically decorated with a variety of Stone Age art, including petroglyphs, various abstract signs and symbols, pictographs, motifs, cupules, cup and ring marks, and other incised imagery.
Typical patterns used in this ancient art included spirals, zigzags and other types of abstract art.
Most portal tombs were covered by a protective mound of earth, but in many cases this has now weathered away.
Dolmens were the original type of cyclopean stone tomb, from which two further forms were developed - the passage tomb and gallery grave.
The most prevalent type of megalithic structure is the portal tomb commonly known as the dolmen.