Boulders were used partially underground to create chambers. Therefore also called chamber graves. A huge semi-square, somewhat flat boulder was laid on top, for cover, giving it a mushroom-like appearance.
In Mecklenburg and Pomerania large numbers of these graves were disturbed, when towns and cities were built. The boulders came in handy for construction and road building.
There are still many left today, even with the extreme density of population in Germany and all over Europe. There are more than 1000 hunebeds on the island of Rügen alone.
The dolmen in Kanghwa (Ganghwa in new spelling) is a northern-type, table-shaped dolmen where ancestral rites were held. It is the biggest stone of this kind in South-Korea, measuring 2.6 x 7.1 x 5.5 meters.