Japan has a very long history. The use of pottery in Japan, for example, started as early as 10,000 BC. The culture which began in 10,000 BC and ended in 300 BC is called the Jomon period. Remains of this culture have been found in many parts of Japan. Central locations were the region of Hokkaido and the northern Tohoku region, where a total of 17 prehistoric sites from the late Jomon period have been found. The 17 locations vary from a settlement to stone circles and man-made hills (also called earthworks).
This article looks at one of these monuments, the stone circle from the late phase of the Jomon period around 2000 BC). The circle stands on a plateau with an altitude varying between 80 to 160 metres, next to the Aomori plain and between the Arakwa and Nyunai rivers. The stone circle is a very large monument with a diameter of 55 metres. The central ring has a diameter of 2.5 metres and is surrounded by another ring 29 metres in diameter. There is a third ring with a diameter of 35 metres. The two outer circles consist of oval stones positioned vertically and horizontally so that they look like a solid wall. This is an unusual construction method for Japan and is still known by the name Komakino.
Excavations close to the stone circles have also revealed floorplans of houses, storage areas and rubbish pits. Remains have also been found of places from where water was fetched, burial sites and locations where pots buried.
In addition to artefacts such as pottery sherds and stone objects used in daily life, other finds have a more religious character such as dolls made from clay, miniature pottery and stones shaped like animals. Also found around the graves were more than 400 triangular stones which indicate some kind of ritual.
Since 1995 these sites are included on a list of protected monuments in Japan. On 27 July 2021 the prehistoric Jomon monuments in the Hokkaido region were added to the UNESCO World Heritage List.
You can find more information in English on the official website.