Nagatoro, Saitama

Where it sits. Nagatoro is a town of fewer than seven thousand people in Chichibu District, western Saitama, strung along a three-kilometre reach of the Arakawa where the river cuts a shallow gorge through the flank of the Chichibu hills. The whole municipality — just over thirty square kilometres — is designated as a prefectural nature park, which is an unusual status for an inhabited town and reflects that the landscape is the local economy. It sits about seventy-five kilometres northwest of central Tokyo and roughly fifteen minutes down the valley from Chichibu city by train.

The rock. The reason Nagatoro exists as a destination is geological. The riverbed here is a broad pavement of crystalline schist, tilted into flat benches and polished by the current, known locally as Iwadatami — rock tatami — because the slabs really do read as green-grey matting laid along the water. The stone belongs to the Sanbagawa metamorphic belt: rocks buried deep in a subduction zone, recrystallised under pressure into a strongly foliated fabric, then exhumed and stripped bare by the river. Nagatoro was designated a National Natural Monument and Place of Scenic Beauty in 1924, and it has a claim to be the birthplace of Japanese geology, because it was here that the first generation of Meiji-era geologists worked out the structure of the Japanese arc. The Saitama Museum of Natural History stands beside the river with the fossil evidence, including the marine mammals recovered from the district's Miocene beds. The area now forms the core of the Chichibu Geopark.

On and in the water. The traditional way to see the gorge is the line-kudari, a descent in a flat-bottomed wooden boat handled by a poler standing at the stern, running from March to early December on two courses of a few kilometres each — one gentle, one with real rapids in it. In the coldest weeks the boats are fitted with covers and charcoal braziers. Alongside them, commercial rafting and packrafting operators run the same water in warmer months, and in summer the pools below the schist benches fill with families. The river is not tame: levels rise fast after rain, and the boats stop running when it does.

Hodosan and the seasons. North of the station rises Hodosan, a modest peak of just under 500 metres with a shrine at its foot whose halls carry dense coloured carving, and a short ropeway that lifts visitors most of the way to the summit. The reason to go up in the depths of winter is the wintersweet garden below the top: thousands of shrubs whose waxy yellow flowers open from late December through February, when almost nothing else in the Kantō region is in bloom, with the Chichibu range and the Kantō plain laid out beyond. In spring, the Kita-Sakura-dōri avenue puts three kilometres of cherry trees along the river, which lands Nagatoro on the standard national list of best blossom sites, and in mid-November the maples at the Tsukinoishi garden turn. Summer belongs to shaved ice: the Chichibu district retains a couple of the last natural ice houses in Japan, cutting pond ice in winter and storing it in insulated sheds, and the shops that serve it draw queues that would be absurd anywhere else.

The name on the manga shelf. Nagatoro's profile outside Japan owes something to an accident of naming: the popular manga and anime Don't Toy with Me, Miss Nagatoro gives its heroine the name of this town, and a steady trickle of visitors now arrives having first encountered the word as a character's surname rather than as a place. Local tourism has been happy to work with the association. It is a lighter-touch version of what happened at Chichibu with Anohana a valley away, and unlike most anime pilgrimage sites there is no specific building to photograph — people come for the name and stay for the gorge, which is arguably the better outcome.

Getting there and timing. Nagatoro Station is on the Chichibu Railway, whose wooden station building dates from the line's opening in 1911 and is a listed structure; the Paleo Express, a steam-hauled service that runs on selected days between Kumagaya and Mitsumineguchi, calls here in season. From Tokyo the usual routes are Seibu's limited express to Seibu-Chichibu and a short hop up the valley, or JR to Kumagaya and the Chichibu Railway west. Everything worth seeing is within twenty minutes' walk of the station or one ropeway ride from it, so a car is unnecessary and parking is scarce in blossom and autumn weeks. Weekdays are calm; spring and autumn weekends fill the boats and the ice shops. The riverside paths are gravel and stone with steps down to the water, and the boats require stepping into an unstable hull, so the gorge is not straightforward for anyone with limited mobility, though the museum and the shrine precinct are manageable.