The site was first noted in the 17th century, and small test units were excavated in the 1950s. But the size and complexity of Sannai Maruyama wasn't understood until the 1990s, when archaeologists were surveying in advance of a baseball stadium.
Archaeologists estimate that only about 40% of the site has been excavated. That has identified over 700 pit-dwellings, 11 long-houses, 120 raised floor buildings, 380 adult grave pits, 800 jar burials for children and infants, 17 stone circles, three clusters of clay mining pits, three road ways built of tamped earth, two water-logged middens and two large midden mounds.
Sources
See the Jomon Timeline and Definition for more specifics on the culture.
See the official Sannai Maruyama website for further information. If you are planning a visit to Japan, the site is open to visitors, with a museum and several reconstructed buildings.
Habu, Junko 2008 Growth and decline in complex hunter-gatherer societies: a case study from the Jomon period Sannai Maruyama site, Japan. Antiquity 82:571–584.
Habu, Junko and Clare Fawcett 1999 Jomon archaelogy and the representation of Japanese origins. Antiquity 73:587-793.
Habu, Junko, Minkoo Kim, Mio Katayama, and Hajime Komiya 2001 Jomon subsistence-settlement systems at the Sannai Maruyama site. Bulletin of the Indo-Pacific Prehistory Association 21:9-21. Free download
Anonymous. The Sannai Maruyama Site: Extraordinarily Large Settlement in Prehistoric Japan. Undated pamphlet available at the Sannai Maruyama site webpage.
