Nemuro Peninsula Chashi Site

The Nemuro Peninsula Chashi Site is a group of 24 chashi, Ainu earthwork enclosures, along the coast of the Nemuro Peninsula in Nemuro, Hokkaido. The group is a National Historic Site and is No. 1 on the list of the 100 Fine Castles of Japan.

History

Chashi (チャシ) is an Ainu word for a fenced enclosure. These sites had several uses: forts, places for rituals, lookouts and places where disputes were negotiated. About 500 chashi sites are known in Hokkaido. Nemuro City has 32, and 24 of them were designated together as a National Historic Site on 26 April 1983. Their exact age is unknown. The city dates them to around the 16th to 18th centuries, which places them among the last chashi built in Hokkaido.

The Nemuro chashi are also studied for their link with the Kunashiri-Menashi uprising of 1789. Japanese who controlled the area had forced the Ainu to work at the fisheries through violence and threats, and Ainu of Kunashiri Island and the Rausu and Shibetsu areas killed 71 Japanese. According to Ishu Retsuzo Furoku (夷酋列像附録, 1798), Tsukinoe, the chief of Kunashiri, built a chashi on the island and prepared poisoned arrows and spears. Nochikusa, chief of Shamokotan in present-day Nemuro, built five chashi to prepare for the fighting. No battle followed. The 37 Ainu who had killed Japanese were brought to Notsukamappu and executed.

The Japan Castle Foundation chose the group as No. 1 of the 100 Fine Castles of Japan in 2006. In 2020 it became part of the Japan Heritage story Sake no Seichi no Monogatari (鮭の聖地の物語), the story of Nemuro as a sacred land of salmon.

The sites

Most of the chashi stand on flat ground at the top of sea cliffs, about 5 to 50 metres above sea level, cut off by a semicircular or square ditch. Many are of the cliff-edge type, menkai-shiki (面崖式), and many combine several ditches into one large site. The group is known for its good state of preservation and for how closely the sites lie together compared with other areas. Two places have walking paths for visitors: Notsukamafu No. 1 and No. 2, and Onnemoto.

Notsukamafu No. 1 and No. 2

These two chashi stand on a headland in Notsukamappu Bay, on a cliff facing the Sea of Okhotsk. No. 1 has two linked semicircular ditches, about 5 metres wide and 3 metres deep, over an area of 70 by 25 metres, with banked earth on their inner side. No. 2 is ringed by a shallow semicircular ditch about 3 metres wide and 0.5 metres deep. Notsukamappu is also known as the place where diplomatic contact between Japan and Russia began: in 1778 the Russian merchant Shabalin landed here and asked to trade.

Onnemoto

Onnemoto Chashi sits on a headland on the west shore of Onnemoto Bay. Earth was heaped on the headland and cut off by a ditch, and two flat areas were made on top. Seen from Onnemoto fishing port its outline recalls osonae mochi (お供え餅), the stacked rice cakes offered at New Year, and it is known as a chashi that has kept its shape well. Pit dwellings of the Okhotsk culture, about 1,300 years old, lie nearby.