The mountains along at the western border of Kanagawa Prefecture draw the limits of the Kantō plain, and long represented an imposing barrier between Japan's old Kansai heartland to the west, and its later core – Edo/Tokyo – to the east. In the bottom corner sits the Hakone caldera, and north of there it is mountains, mountains and more mountains until the Sagami River and the pass through to Yamanashi.
Outside Hakone's northern rim runs 759m-high Ashigara Pass (足柄峠): a deep and narrow valley, and in old times the most accessible gap in this barrier. But with its susceptibility to eruptions of nearby Mount Fuji, and the rise in significance of Hakone and Odawara, this route was gradually eclipsed in favour of the Tōkaidō highway through Hakone itself.
You can read about that Hakone passage here, with its nasty Edo-period checkpoint. The mountains of Hakone's northern rim, Mt. Kintoki and Myojingadake and the ridge of bamboo between them, as well as Hakone's central lava dome of Kamiyama, also feature in that article.
Those are all on Ashigara Pass's south side. A different mountain stands on its north: Yaguradake (矢倉岳), a peak with a funny domed head.
Yagura (矢倉) means “watchtower” or “turret”. I do not know if such a structure once stood here, but you would struggle to find a better place to put one. Yaguradake's summit commands an open panorama, arcing from the Tanzawa Mountains to the east, across Odawara and Sagami Bay, then down Ashigara Pass and across to Hakone's mountains opposite; and finally round to the west, where it affords a remarkable view of Mt. Fuji and its surrounding lowlands.
|Facing southeast: the city of Odawara, and Sagami Bay in the background.|
|Facing south, towards Hakone. On the left is Myojingadake, and on the right Mt. Kintoki, joined by Hakone's northern ridge. Ashigara Pass is down below. Lurking in the middle background is Kamiyama, Hakone's central lava dome and highest point.|
|Facing west, towards Gotemba (Shizuoka Prefecture) and Mt. Fuji.|
To control this vantage point is to control Ashigara Pass. From here you can spot anything which tries to get through the ravine below, be they armies marching under rival warlords or disgruntled daimyō (feudal-era lords) rolling in from the west to invade the capital; or equally, any response therefrom dispatched by the shogun. From here your signals would reach far in both directions, across the uninterrupted flats, or even to ships out at sea. And there are only few ways up the mountain, each of them steep, dense with foliage and very defensible. And on top of all that, when it's someone else's shift, this site gives you the privilege of a sunlit nap on the grass or a classic picnic lunch with Mt. Fuji in the background.
This is a moderate hike. The way up Yaguradake is steep, but the ground is gentle, and it only takes an hour and half to climb at gentle pace. To get there, take the Odakyu Line to Shin-Matusda station (新松田駅), then go to the bus stops outside the North Exit and take the Hakone Tōzan Bus bound for Jizōdō (地蔵堂). (Timetable here: the correct bus is the one with 地 next to its times.) Get off at Yagurazawa (矢倉沢), where the route starts. The bus ride takes about 27 minutes and costs 660 yen.
After climbing the mountain, the fuller, most fulfilling route would then be along the forested ridge to the north and east, arriving in Yamakita village near the famous and beautiful Shasui Falls (洒水ノ滝); but a certain problem makes this route impassable at present, as we will see, so I cannot currently recommend that east trail. Instead you should go down the way you came, or take the other path down into Ashigara Pass itself, where there is probably a bus stop.
From Yamakita bus stop, cross the road and head north (as in the photo) into the village, crossing the Maeda Bridge (前田橋). Turn left when you reach this house, which has the way to Yaguradake painted upon it.
From here you snake north and west through the houses, following more signposts on corners, until you reach the Shiroyama Shrine (白山神社), a Totoro-esque installation hidden up some steps in a tall grove.
|The stairs to Shiroyama Shrine.|
The trailhead starts to the left here. Follow the road as it leads up through bamboo and curls to the right, taking in the hillsides and the contrast between the colourful deciduous forests and the dark green blankets of sugi plantations. When it forks, go left to reach a metal gate next to a tea plantation.
|The signs warn of hornets (すずめばち) and wild boars (いのしし). There are further warnings of wasp nests over the next few hundred metres. None were seen on this walk, but suzumebachi hornets can be aggressive, so be prepared.|
Now comes the straightforward slog up the mountain through rich and varied forest. There is only one path, so no danger of getting lost.
And at the top, you come out at the aforementioned sunny and grassy summit, the perfect spot for a well-earned lunch. Make sure to study your maps while there and learn the surrounding geography, for this is one of those special places where it lays everything out in front of you, ripe for understanding.
From here you can either go back down the way you came, or take the opposite path (steep but short) down the summit's west flank to Yamabushidaira (山伏平), a junction where a left turn leads down into Ashigara Pass. For reasons you will see, you should not – at least, not yet – do as we did and turn right, onto this lovely ridge with its rocky stream and haunted evergreens.
That route eventually comes out at the “central wide space” (セントラル広場), where it becomes a mountain road past several thematic planted areas, together making up the “21st Century Forest” (21世紀の森). From that area there are two paths down to the waterfall: one along that road, and another off a side-path by an NHK television tower.
|There is a viewing platform along here that provides an excellent position to watch the sun set behind Mt. Fuji.|
|The first path to the waterfall is just left here, by this pavilion.|
|Yamakita, the intended final destination of this walk, near the waterfall.|
|The second path to the waterfall is next to this TV tower.|
The problem is that both paths to the waterfall are currently closed. Apparently a landslide has made the falls inaccessible. This was trouble in more ways than one, given first that there was no advance indication of this, and second that there are no alternative ways east off the ridge into Yamakita. From that point, the only available detour is to stay on that road, which winds south, then west, then south – that is, in completely the wrong directions – to come out of the mountains on the wrong side, before it staggers east back to settled areas, and then winds north round the mountains to Yamakita in considerably longer and more monotonous fashion than is fair.
We were saved some trouble on this occasion by some very helpful passing locals in a vehicle (transporting mountain vegetables and searching for a lost dog), but this issue means that the ridge path northeast from Yaguradake should not be considered at this stage. If at some point they fix that path to the waterfall – and I sincerely hope they do – then the walk as a whole would probably take about five hours, and rejoin the Kantō Plain at Yamakita Station on the JR Gotemba Line, which you can ride for two stops to Matsuda, then change for the Odakyu Line back to Tokyo.
If anyone happens to visit the waterfall/21st Century Forest area in a car, and finds that the path between them has been repaired, please leave a comment here to inform me so I can update the route guidance accordingly.