Zao Hot Springs
It is arguable to say that while Mount Zao attracts its share of ski junkies and snow monster hunters in the winter, the innumerable natural hot springs of the area draw just as many pilgrims, in search of these supposedly miracle waters. In and around the rustic ski resort of Zao Onsen are five different subterranean sources and forty-seven individual hot springs. The hot springs in Zao Onsen run from traditional to posh, and while onsen acolytes tout these “Springs of Beauty” as medicinally efficacious in everything from skin disorders to “weak children,” they are undoubtedly soul-searingly luxuriating.
These hot springs may have been discovered as far back as 110 AD, when itinerant samurai passing through the area discovered a warm stream flowing through the forest. They traced the stream back to its source, in the heart of what is today Zao Onsen village, and is now the site of the Kawarayu public bath house. There are in fact three public onsen in town, all wood constructed houses with individual bathing pools for men and women (which is common to most onsen in Japan). Along with Shimoyu and Kamiyu, these unmanned public houses all charge a paltry ￥200 on honor system upon entry, and are fantastic for a traditional, local-style onsen experience.
Volcanic activity deep within the mountain powers these springs, and one can see evidence of the last major eruption, dating back to the 18th century, in which Zao’s crater lake was formed. The lake can be accessed by car or trail in the non-winter season, and during winter with a trusted trekking guide. The lake is also known as “Five Color Pond” on account that the water color changes with the weather and seasons.
But down below, at just over 800m, super-heated, ultra-mineral rich waters gush forth, and fill an number of streams that run through the village with plumes of steam. The springs are unique for their especially high acidity, and aluminum, chloride, and sulfide content, all of which many folks claim can improve the skin and heal wounds. Owing to its high sulfur content, the waters’ let’s just say slightly pungent scent is love-it-or-hate-it for some visitors. The naturally milky-white water does leave skin feeling smooth and a little slippery, some might say, just like a baby snow monkey!
Apart from the public houses in the heart of town, there are a huge number of day-use onsen to choose from, price of entry usually ranging from just ￥400-600. Some hotels include their own private onsen as well. My advice for anyone taking an extended stay on Zao is to explore a different one each day. Many onsen include rotenburo, or outdoor bathing areas where one can enjoy their soak amidst natural beauty. A great place to start is Shinzaemon No Yu, located right across the street from the Zao Chuo Ropeway Station. Lazing in the stone-built rotenburo, surrounded by snow piled high in the winter is as meditative as it is invigorating. This onsen also hosts a great foot bath out front if you just feeling like resting your weary feet somewhere for a moment.
Another great rotenburo can be found just a short, steep jaunt from the main road at Genshichi No Yu. You’ll quickly be at ease in these milky-blue pools, as spring water comes up from stone stacks in the center of the pool. For the ultimate forest hot spring adventure though, Zao Onsen Dai Rotenburo can’t be missed. This onsen is the highest in the area, situated in a little valley along a stream and surrounded by forest. After taking a long series of stairs through the forest you’ll soon arrive at this tranquil paradise. Due to the high elevation though, the rotenburo is closed in winter, from December through march.
Public bath houses are open 10:00-10:00, daily. Price: ￥200
Links to selected day-use bath houses:
Shinzaemon No Yu
Genshichi No Yu
Zao Onsen Dai Rotenburo