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The trailhead after a lucky late-February fresh snow
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One of two routes to the valley: I took the high road
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Winter wonderland
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On the right track. The trail is very well-marked leading up to the valley.
Along the way, you'll encounter a great number of dam and erosion control projects. The rivers that begin in the Nikko mountains often flood during the spring and rainy season, and in the past have even threatened towns as far downstream as Tokyo. Some of the dams here date back over 100 years and are now designated as national cultural assets.
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One of many dams along the river
After about 90 minutes of hiking, I found myself at a small landing with steps leading down to the approach to Unryu Keikoku itself. From this point, the trail leads on top of the valley stream bed itself, jumping back and forth over still-flowing water exposed under the snow and ice.
This was good spot to put on crampons. From late December through early March, a pair of at least 6-point crampons strapped to the bottoms of your boots will help immensely to provide extra traction on the slippery terrain ahead, and allow you to explore deeper into the valley in snowy or icy conditions (which are common). Snowshoes, on the other hand, are more likely to get in the way than help here as the rocky, narrow paths don't usualy afford enough room or deep snow to be useful.
And with my crampons fastened, I headed into the valley of ice, snow and clouds.
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Hikers putting on crampons
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Heading into the Unryu Valley
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My 10-point crampons came in very handy on this snowy day. While lighter crampons can also work, the more points, the more terrain you can tackle, like ascending steep valley walls deeper in. (Thanks to my lovely fiancée for outfitting me!)
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The icy entrance to the valley
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Otherworldly
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Frozen meets flowing
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The treacherous, beautiful path forward, with walls of ice looming overhead
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Behind the ice falls
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Unryu Waterfall (Unryubaku) towering in the background
After passing among the largest ice columns, the view of the frozen Unryu Waterfall itself was a pretty incredible sight to behold. From this point, the path becomes more treacherous and challenging, and in fresh snow (like I encountered), can be very difficult to find at all. I managed to find a snowy slope leading up a bit further which led (with some improvisation, and liberal use of my crampons) right up to Unryu Waterfall itself. On weekends, this area can become bustling with ice climbers scaling the frozen falls.
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Arena of the ice giants
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Unryu Waterfall up close
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More frozen falls cascading down the valley walls deeper and deeper in
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Back on the valley floor enjoying some hot coffee with other friendly hikers (thanks again, guys!)
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Hiker Tom getting shots of the ice
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Pretty unforgettable
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One last look up
To see the waterfalls while they are frozen, the best timing for this hike is between late December and early March. Temperatures can reach well below freezing here, so warm winter clothes, gloves, and sturdy waterproof boots are a must. 6-point or higher crampons are also highly recommended when the path is snowy or icy (which may not be obvious until well into the hike).
Rock slides are a frequent occurence in this valley. It's safer to move quickly when walking through exposed areas next to cliffs without lingering longer than necessary. When walking near frozen waterfalls and ice formations, remember that these can break and fall at any time, especially near the beginning and end of the season and in warmer conditions. Be very cautious when approaching or going under overhanging ice; if you hear any cracking sounds, get away as fast as possible.
And, of course, don't climb on ice without ice climbing training and appropriate gear.