There’s a very old urn sitting at the bottom of Lake Biwako in Japan, and archeologists are stumped as to why it’s there.
The photo of the Haji urn found in Lake Biwako [Photo by Ritsumeikan University]
Sometimes, archaeological finds just aren’t straightforward. Many archaeological finds are amazing but not surprising, while some are just a head-scratcher. A report by Asahi Shimbun says that an underwater robot was able to capture photos of an ancient Haji urn about 30 to 40 centimeters in height, 71.5 meters down on the lakebed. Haji pottery is unglazed and characteristically reddish-brown due to the exposure of minerals in the material to fire. This type of pottery came into existence in the fourth century AD and found prominence during the Heian period, which lasted from 794 AD to 1185 AD.
A Shinto shrine gate rises through the surface of Lake Biwako [Photo by Toru Hanai, Reuters]
The urn found at the bottom of Lake Biwako may date to the seventh or eighth centuries, sometime between the Nara and Asuka periods. Interestingly, other pieces of gray-black pottery, believed to be Sue pottery, were also found in six spots around the Haji urn.
The discovery site was at the northern part of the lake, in an archaeological site called Tsuzuraozaki Kotei Iseki. Lake Biwako is Japan’s biggest freshwater lake, and it boasts strong currents. These strong currents may be the reason why the urn was unearthed in the first place. It’s also the reason why robots, instead of humans, are the ones exploring that part of the lake’s depths.
This isn’t the first piece of pottery that’s been found in the same archaeological sights. Many pieces belonging to the Jomon Pottery Culture Period and the Heian period have been unearthed since 1924. These pieces, found at depths of 10 to 70 meters, have often been caught in fishing nets.
An example of Sue pottery
What’s interesting is that these periods cover large swaths of time. The Jomon Pottery Culture Period, for example, lasted from about 8000 BC to 300 BC. Meanwhile, pottery techniques from Korea traveled over in the fifth century, marking the advent of Sue pottery.
Archaeologists still don’t know why these pieces of pottery that range from such diverse time periods can be found in a single archaeological site. A possible explanation is that the lake was once a settlement that has eventually become submerged, while another possible explanation is that the pottery pieces were part of some “obscure ritual”. Of course, it’s also possible that the explanation is a simple one: that the lake was the disposal site for unused pottery.
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