Sunday, July 12, 2026

A meizanologist's diary (136)

2 April: sailing south by boat, riding north on horseback (nansen-hokuba, 南船北馬) is a four-character expression that describes the urge to madly rush about. This being precisely the impulse that overtakes me when a Japanese Rail Pass is about to expire, I let the Hokuriku Main Line waft me down to Kusatsu.


Although it may seem off-script for a meizanologist to visit a museum dedicated to a lake, an exception has to be made here. As a geological phenomenon, Lake Biwa is remarkable not just for its size – the largest freshwater expanse in Japan – but for its age. Most lakes fill in quickly, yet Biwa-ko has endured for four million years, helping it to sustain sixty or so endemic plants and fish.


An exhibit in the endemic Lake Biwa Museum explains why. The reconstructed site of a geological fault line shows how the lake’s rocky floor has kept sinking over time, at roughly a metre every thousand years. 


I’m reminded of the folk tale that a Godzilla-like giant Daidarabotchi excavated Lake Biwa, all in a single night, and piled up Mt. Fuji from the left-over spoil-tip…


Back in the museum, a diorama takes us into the deep past, when elephants roamed through forests of metasequoia and crocodiles lurked at their watering holes. 


One of the elephants later caused a sensation. In 1804, when people found its fossilised bones on the lake’s western shore, they thought at first they’d found a dragon.


From geology, we move into historical times. In the feudal era, long maruko-bune plied the lake, moving as elegantly if not quite as fast as a modern N700


There’s also a typical lakeside house, set up as it was in 1964, when water came from a stream and the nightsoil went straight onto the vegetable patch. In his Japan Journals, Donald Richie recalls how this latter practice led in the late 1940s to what he wryly calls a reverse Occupation…


After an hour or so among the cultural exhibits, I decide to make shorter work of those on insect and plant life.


After nodding to a giant dragonfly, I follow the children who are tugging their parents in the direction of the museum’s famous aquarium. 


Somehow I manage to miss an encounter with a giant catfish, the so-called lords of Lake Biwa.


This may be because I’m distracted by a friendly seal, who seems to be inspecting his visitors as curiously as they are inspecting him. Surely he can’t be an endemic? But, no, the seal is a Russian émigré, imported from Baikal, presumably a Twin Lake. I hope he isn’t missing the depths and ice sheets of his native waters.

Patrons should note that there is only one bus an hour from the museum back to Kusatsu station. Before catching it, I stroll out onto the outdoor viewing platform. A brisk spring breeze is whipping up white-capped waves out on the lake.


Under the clear sky, I start to appreciate the size of this lake. It seems entirely reasonable that scooping it out would leave you with a Mt. Fuji-sized spoil-tip. How sad that the volumes don’t match up. No, not at all – the savants have calculated that you’d need to dig out something like fifty Lake Biwa basins to pile up just one 3,766 metre-high mountain. Now even for a Daidarabotchi, that sounds too much like hard work...


Wednesday, July 8, 2026

A meizanologist's diary (135)

29 March (cont): on the way home, we stop at the Hill of Oshitoishi. The kanji on the road sign spell out its name as “push-door-rock”. However, as the car hammers down the last few kilometres of dirt track, I fear it's the shock struts that are pushing their luck.


Still, we arrive at the car park in one piece and fork out three hundred yen each at a makeshift booth. In return, the attendant hands over a brochure, pointing out to us the bit about Oshitoishi’s mysterious alignment along paths representing water, fire and the sun. These, the brochure suggests, may be divine paths created during the Jōmon period.


For my money, the “Path of the Sun” is the one to watch. The brochure shows it extending directly from this hill through the Tokugawa mausoleum at Nikkō and then right on out into the Pacific. Follow it far enough, I reckon, and you’d surely end up at Glastonbury.

Taking leave of the amiable attendant, who has also lent us a brace of compasses, we wander uphill in search of stones. 


The brochure says that a 360-degree panorama awaits us up there, along with a sacred Jōmon site and the power spot of Oshitoshi. And by way of background, it relates that

The Minamioguni Town Board of Education discovered mysterious engraved patterns on the megalithic group at Oshitoishi Hill. They commissioned Kei Koda, president of the Japan Petroglyph Association, to investigate, and it was confirmed that these were Sumerian characters (petroglyphs). Subsequently, this megalithic group was recognised by international academic societies, including the UNESCO Society for Petrology and the Petrology Societies of the United States and Canada, as a prehistoric megalithic cultural site consisting of nine artificially arranged stone rows.


Artificially arranged or not, we are grateful for those stone rows. Fatigued after our vigorous morning hike, we arrange ourselves over the first of them for a rest. 


Although the sky has clouded over, Oshitoishi delivers handsomely on its promise of a 360-degree panorama. We can still see the central peaks of Aso-san to the south, while eastwards rise the volcanic tumps of the Kujū range. 


The view is spacious, austere and bracing all at once. It explains why talented photographers like Kawauchi Rinko keep seeking out these vast and rolling hillscapes…


Behind us, just upslope, is the Kagami-ishi that we’ve come so far to see. Now it’s time to inspect it. Again, I reach for the brochure to see what mysteries this “mirror stone” may reflect:

The Kagami-ishi bears Sumerian inscriptions representing a serpent god and a sacred bull. Our local place name is Nakabaru in Minamioguni Town. As the serpent god is read as 'Naga' and the sacred bull as 'Baal', it is thought that the place name Nakabaru is derived from the Sumerian characters.

To the untrained eye, all that can be seen are flecks of lichen and some rune-like rills and cracks. But that doesn’t mean that the bull isn’t there, or the serpent. It’s a fact that the Sumerians and the Jōmons overlapped for more than two millennia – allowing ample time for a venturesome Sumerian to sail his (or her) reed boat as far as Nagasaki and hop on the Shinkansen to Kumamoto, chisel in hand…


This reverie is interrupted when the Sensei hands me a compass. Momentarily bemused, I take another glance at the brochure.

The Oshito Stone is 5.5 metres high, has a circumference of 15.3 metres, and forms the centre of a group of megaliths. The North Star lies directly north of its apex. Strangely, the magnetic field around this stone is abnormal, so that a compass spins wildly when brought near it. Legend has it that it will rain if you try to climb the stone. It was formerly known as 'the demon's beanbag', and has attracted people’s admiration since ancient times.

Naruhodo: the compass should swing if we bring it near the rock. But nothing would be less surprising – all the rock around here is andesite, as it is in half of Kyushu, so it’s more than likely to be magnetic. That said, the Oshito is a quite magnificent megalith. In days gone by, warlords would have fought for the privilege of planting it in their gardens.

I’m about to give the compass a whirl anyway when we’re distracted. A mother – and is it just me, or do I not detect something faintly Sumerian in her lineaments – is handing a spoon to her pig-tailed daughter. Just an ordinary tablespoon, mind you, but given that we’re standing at a veritable ganglion of ley lines, something is bound to happen.


Nor are we disappointed. Steering her daughter by the shoulders, the mother begins to shuffle round the Oshito Rock in a clockwise direction. The little girl walks on ahead, holding the spoon upright in both hands like a votive candle. And right then and there it happens – the spoon bends and wilts in her hands like a plant you’ve forgotten to water.

At least, that’s how the Sensei later describes it to me – she actually saw it happen, but I’m looking elsewhere at the critical moment. In fact, I’m looking at the handwritten sign that somebody has left at the foot of the rock. 'Supūn wo okanaide,' it says – please don’t leave your spoons.


I look at the Sensei. Something seems to be troubling her. "That sign," she says, 'it’s ungrammatical. It should read Supūn wo itte okanaide." Don't leave without taking your spoons with you.

So there it is. Nobody can say for certain whether the Oshitoishi will bend your spoons. So don't blame me if it does. Or doesn't. One thing can be avowed, though - once you get within the old stone's spot of power, you need to watch out most carefully for your sense of style and syntax...






Tuesday, July 7, 2026

A meizanologist's diary (134)

29 March: the day after climbing Takadake, our hosts drive us back towards Mt. Aso. This time, the idea is to take in the whole massif at a single glance. The car is parked near a spacious tourist pavilion offering the usual array of leaflets and indigestible comestibles.


The place used to be known as the Tōmigahana (look-off nose) but in 1922 the writer Tokutomi Sohō rebranded it as the Daikanbō (great viewpoint), apparently at the local mayor’s request.


The mayor was right. For this viewpoint does deserve a dignified appellation. And it takes a moment before we can calibrate our eyes to the sheer scale of the panorama it offers. 


We’re standing on the brink of the “gairin-kan” – the outer rim of Aso’s giant caldera – and far off, over a sea of morning haze, float the five central peaks, including the two we visited yesterday. Everything within our gaze is part of one huge volcano.


“So they really do look like a reclining Buddha,” says the Sensei. We agree that the crags over on the left of the central mountains do indeed resemble an upturned face. The likeness is so often remarked that it even has a name: the Nehanzō, although the bronze versions seen at temples are usually lying on their sides.

Whether recumbent or reclining, no Buddha was mentioned by the celebrated poet and painter Kosugi Hōan when he came this way in 1930, his visit sponsored by the Kyushu Electric Power Company. Rather, he beheld:

a vast space, like the bottom of an urn, in which the caldera unfolds. Black smoke churns up in the centre to scorch the heavens. Under these incense fumes, sent up by the earth’s deity as if from some great censer, the five peaks of Aso vie with one another, each with its individual beauty.

As for the vast caldera’s backstory, Kosugi had this to say:

Originally, the crater plain, measuring four leagues east to west and six leagues north to south, covering forty thousand chō, was formed by a massive collapse. After the collapse, the five peaks that now exist erupted in the centre. Thus, surrounded by the circular outer rim, this plain should form a snake’s eye shape. However, Neko-dake, one of the five peaks, rose up and broached the outer rim near its southern edge, breaking the snake's eye shape at that point…


And pretty much the same account is related to us today by the Great Viewpoint's instructive signboards:

In Aso, the land subsided to create a caldera because of four super-eruptions occurred between about 90,000 years ago to about 270,000 years ago … The pyroclastic flow at that time spread the northern part of Kyushu island and volcanic ash curled up to sky covered all over Japan …The biggest pyroclastic flow of Aso (Aso-4) is the largest in scale in Japan in the past 100,000 years. Volcanic deposits would have reached the height of a four to five storey building if they were distributed uniformly in Kyushu island…

The collapse thesis, we later learn, was bolstered by the work of Howell Williams, an Anglo-American volcanologist who during the 1940s explained the formation of Oregon’s Crater Lake. More recently, though, a new generation of savants have objected that Aso could never have been so reprobate as to collapse in slavish imitation of a foreign model. Instead, as any self-respecting mega-vent should, it must have exploded heroically onto the scene...

But these revisionist views must be considered at a later date. Right now, our host is waving us back to the car. We are soon driving across that flat caldera floor, which is – according to the application to have Mt. Aso listed as a UNESCO world heritage site – “an excellent site for learning about how humans live in a volcanic area”.

From what we can see from the speeding vehicle, the humans are living here much as they do elsewhere in Japan – in the same prefabricated houses, under the same tangle of overhead wires, and amid the same proliferation of vending machines. Speaking of which, it must surely be time for a coffee…


Already, however, we are slanting up the slopes of those five central peaks. Sliding by on the right is the parasite cone of Komezuka. “Rice heap” is a good name for it, chiming as it does with the mini-volcano’s family-friendly scale. Its bonsai proportions somewhat relieve the oppression of its pitilessly vast surroundings.

Parking the car near the Aso Volcano Museum, we set off across a grassy paddock, dodging the errant pony riders from the nearby dude ranch as we head for the local eminence of Eboshi-dake. 


Our path up the easy ridge is fringed with Japanese andromeda (asebi), the so-called drunken horse tree. Presumably the ponies are kept well away from them. 


Although it rises only a paltry few metres above the carpark, Eboshi-dake qualifies as one of Aso-san’s Five Peaks. 


Even better, it commands fine views in all directions. Behind us, we now see that what we took to be a grassy paddock is in fact the crater floor of a retired volcano, a kind of caldera within the caldera. East of us, and fortunately downwind, is Nakadake, still venting its corrosive fumes high into the hazy air. 


And in the opposite direction, riding hull-down on the dust horizon, are the upperworks of Unzen, the westernmost of Kyushu’s volcanoes. A conveniently placed signboard helps us locate it.


All this looking-off works up an appetite. We hurry down Eboshi’s eastern ridge, looking for somewhere to eat our lunches. 


Alas, several of the benches considerately installed for that purpose have burned to the ground. They apparently get torched during the annual grass-burnings (noyaki) that are carried out to prevent these uplands tumbling down into scrub. 

When we finally reach an uncharred picnic place, we watch an elderly couple struggle up a variation route on another nearby hill. Not for us, we decide, as we tuck into our bento boxes. Although we have been hiking almost as efficiently as we did thirty years ago, just one of the Five Peaks will do nicely for today. Besides, we still have a Place of Power to take in on our way home.






Monday, June 15, 2026

A meizanologist's diary (133)

28 March: the Sensei takes charge of the plan. We’ll drive up to the Sensuikyo parking lot at 800 metres or so, then tackle a ridge route up to Takadake, at 1,592 metres the highest of Aso-san’s Five Peaks. 


At mid-morning, we park the car soon after passing a stupa dedicated to world peace by a local monk.


It seems that Nichidatsu Fujii, who was from Aso City, built more than seventy of these giant reliquaries around the world, in Europe and America as well as in Asia. Alas, judging by current events, even that considerable number may not have sufficed.


A whiff of sulphur greets us as we get our kit out of the car. And just in case we haven't noticed, the sign at the trailhead gets straight to the point: “Release of volcanic gas (S02: sulfur dioxide) has been continuing around Mt. Aso. Be ready to protect yourselves individually with full understanding of the risk from volcanic gas.” 


A nearby row of memorials brings the message home: accidents can and do happen around here.


Our ridge is like the scaly back of some gigantic sea beast. We weave to and fro, seeking out a line before we realise there’s a series of painted yellow arrows to guide us. We’re working our way upwards on solid lava flows: nothing but knobbled black rock, except for a patch of withered yellow grass here and there.


The heat and the stench intensify as we struggle upwards. Flies buzz round us. And now we can see where the fumes are coming from – the roiling clouds of asphyxiating vapour spilling over a ridge crest to the right. Although Aso’s main crater is still kilometres away, it must sit exactly upwind of us.

Like the mountain in Dante’s Purgatory, the slopes ease a bit as we gain height. Gradually, Nichidatsu's stupa shrinks down into a white wen in the hazy depths below. 

When a headwall starts to loom above, we decide it’s too tiresome to tackle right now and sit down for lunch. I must be having a bad day: having forgotten my water bottle on our hosts’ kitchen counter, I now discover that my bento box has leaked into my pack. The lunch is still delicious though: Hirai, the local bentoyasan can only be recommended.


I must be looking debilitated: the Sensei passes over a “bakudan” (bombshell) rice ball to supplement the bento. This too goes down gratefully. After lunch, a cool breeze starts to blow, dispelling the sulphurous fumes, and we pick up the pace. 


When we arrive in the shadow of the headwall, the yellow arrows direct us rightwards, up a ramp like Mt Asama’s famous J-band. Judging by Canto IV of his Purgatory, Dante must have been here too:

Squeezed in between the tight walls of the pass,
we struggled upward through that broken rock,
using our hands and feet to climb the ground…


Illustration by Gustave Doré for Canto IV of Dante's Purgatory

A few hundred metres more takes us to the summit ridge. The breeze strengthens as we walk over to Takadake’s trig point – there doesn’t seem to be a shrine up here. Perhaps the scenery is too desolate even for a god.  Then we walk carefully over the boot-shredding lava edges to the descent path. 


All of us have visited Aso-san before – heck, I even cycled across the massif in my student days – yet it’s still impossible to get a grip on this volcano’s dimensions. Mote-like figures on a ridge between us and the steaming crater dramatise the gargantuan scale...

Gargantuan? Adjectives crumble under the load of representing this scene. Other Japanese volcanoes - yes, even the boss of them all - fit into a surrounding landscape. Here, as far as the eye can reach, all you see is the volcano. 




A series of descending ridges bring us to the crest above the main crater. This vast declivity is still venting nonchalantly to itself, the fumes thinning and thickening almost as if the beast is breathing. Occasionally, a mushroom of vapour writhes silently upwards and drifts off with the wind. 

Still groping for an adjective to qualify this spectacle, I settle on "Dante-esque". Or should that be "Dantean"? Overused, admittedly, but like the poet's Inferno this scenery doesn't belong to the world we know. 


I stand there enthralled until a sulphur-laden gust blows my hat away. Probably one shouldn’t hang about here too long. Dilapidated shelters along the concrete-surfaced path bear witness to an eruption in 1958 that did for twelve of Aso-san’s visitors.


And over yonder, like a line of monuments, are the pillars of the Mt Aso Ropeway, now abandoned. After starting up in the same year as the eruption disaster, it managed to keep operating for half a century or so, in the face of corrosive effusions, ash falls and earthquakes. But the volcano won in the end.


The Sensei and our host are already far down the path. I hurry after them, putting as many metres as I can between ourselves and that monstrous crater at our back.