Oyu Stone Circles

From the road you might drive past without noticing anything. The two circles at Oyu are made of river cobbles laid out in small groups, not standing monoliths, and they sit flat on a grassy terrace above the Oyu River in Kazuno, in the northeast corner of Akita. They face each other about 130 m apart, with a road running between them. Manza, to the west, is up to 52 m across; Nonakado, to the east, is up to 44 m. People of the Late Jomon period built them between about 2000 and 1500 BCE, and around the rings archaeologists found post buildings, storage pits and graves laid out in concentric bands, along with clay figurines and clay tablets used in rituals.

The detail that sticks is the sundial-shaped stone arrangement beside each ring. A line through the centre stones of both circles and the two sundial stones runs roughly towards the midsummer sunset, which has led some researchers to argue the builders were watching the sun. The site is one of the 17 parts of the Jomon Prehistoric Sites in Northern Japan, inscribed as World Heritage in July 2021.

Start at the Oyu Stone Circle Museum, the visitor centre by the site. Entry is free and the exhibition hall costs 320 yen. Use the toilets there: to keep the place looking prehistoric, the city puts no toilets and no explanation boards on the site itself. Without a guide the pattern is hard to read, so join one of the free volunteer walks, six a day from 9:10, no booking needed (11 April to 23 November in 2026). The circles sit behind an electric fence, close at night and close for the winter after that; the museum stays open in winter but shuts on Mondays.

The catch is transport. The nearest station with a bus is Kazuno-Hanawa, about two hours from Morioka on the JR Hanawa Line, and from October 2026 the bus does not run at weekends or on holidays. With a car, the Oyu Onsen hot spring inns are a few kilometres away, and Lake Towada is a longer drive beyond them.