Towada-Hachimantai National Park

A national park in two separate pieces spread across Aomori, Akita and Iwate, both of them volcanic, both of them buried in snow for a third of the year.

The Towada half centres on a caldera lake 327 metres deep, the third deepest in Japan, sitting in a crater inside another crater. Water leaves it through the Oirase gorge, and the 14 kilometres of walking path beside that stream from Nenokuchi to Yakeyama is the best-known walk in northern Honshu: moss on everything, boulders in the current, and a series of falls with Choshi Otaki the largest. The road runs alongside, so you can walk a section and take the bus back. Late October is when the beeches and maples turn, and the road fills with coaches.

West of there the Hakkoda mountains carry a ropeway to a plateau that ices over into snow-covered fir formations by February. At their foot, Sukayu Onsen has a single cedar bathing hall known as the thousand-person bath, cloudy, strongly acidic and traditionally mixed, which puts some visitors off and is exactly why others come.

The Hachimantai half is a high volcanic plateau of crater lakes and steam vents, crossed by the Aspite Line road, which reopens in April between snow walls several metres high. Tamagawa Onsen near the boundary produces the most acidic hot spring water in Japan and people lie on the heated rock beds there for their health.

Bus services exist but are seasonal and thin. A car makes the difference between seeing one part and seeing the park. Winter closes many of the roads entirely.