4180 Travel Guide

The Oshi were the sacred hosts and guides of Fuji worship who received and led climbers along the old Yoshida trail; around Fujiyoshida (Kitaguchi Hongu) their old residences survive as living heritage of climbing culture. The Former Togawa family residence, a component of the Mt. Fuji World Heritage site built in 1768, is a representative Oshi house with a Fujisan shrine room and spacious guest rooms, displaying Fujiko documents. Today open as a museum, it is a door to understanding 'Fuji faith'.

This is the Biodiversity Center of Japan, part of the Ministry of the Environment, not a museum devoted only to Mt. Fuji. It sits in the Kenmarubi district on the mountain's northern foothills, sharing a site with the Yamanashi Institute of Environmental Sciences, and its remit is national: the surveys of the natural environment known as the Green Census are compiled here, together with long-term monitoring of plant and animal distribution, vegetation and ecosystems, all opened up to the public. Specimens, models and a video theatre explain Japan's natural gradient from subarctic to subtropical, while a reference library holds the original survey reports. It suits families doing nature study or walkers wanting to understand the foothill ecology before climbing Fuji; anyone expecting a gallery solely of Fuji's endemic species will find the scope broader than expected. Entry is free, 09:00-17:00, but the closure rule matters: from November through April it shuts every Saturday, Sunday and public holiday, and also from 28 December to 4 January, so a winter trip on a weekend will most likely meet a locked door. Twenty free car spaces sit in front; Kawaguchiko Station is fifteen minutes away by taxi. The Yoshida lava tree molds, fenced for most of the year and open on 29 April, are close by, so the two can be judged together before making the trip.

The Yoshida lava tree molds are not trees at all but cavities left by lava. When Mt. Fuji erupted in 937, the Kenmarubi flow swept through a forest and engulfed the trunks; the wood burned away and the cooling lava kept their shape, with several trees overlapping to form longer tunnels whose ribbed walls look like the inside of a body. The largest, called Yoshida Tainai, runs close to 65 metres. Together with 62 other cavities nearby it forms the Yoshida Lava Tree Mold Group, a national natural monument and, since 2013, a component of the Fujisan World Heritage listing. Fuji-ko pilgrims crawled through it as a return to the womb and a rebirth, which is where 'tainai' comes from; in 1892 the Marufuji Sooko congregation adopted this cave in place of the nearby Funatsu Tainai, and pilgrims and local oshi guides have cared for it since. The present access rules matter more than the geology: a fence closes the entrance for most of the year to protect the molds and keep visitors safe. The single day the cave opens to everyone is 29 April, the Yoshida Tainai Festival, with Shinto rites and a burning ceremony by Fuji-ko believers; on any other date a visit requires prior permission from Fujiyoshida's cultural heritage office. There is no dedicated car park. From Nakanochaya it is a thirty-minute walk along the Yoshida ascent route, so wear proper shoes. Outside the festival, arriving unannounced means seeing a fence and trees; the year-round Funatsu Tainai nearby is the practical alternative.