Thanks to the abundance of volcanic activity all along the Japanese archipelago, Japan’s ancient custom of bathing in hot springs is legendary. The mineral-infused water is believed to have healing powers, and soaking in them is a weekly practice for many. In the United States, most hot springs are left in a more natural state, many requiring at least a notable drive, if not also a hike to reach. In Japan, large bath houses are built up around spring sources to accommodate visitors, and these can often be found within city limits. Many larger ones feature restaurants, shops for purchasing souvenirs, such as locally produced food products, and rooms in which guests can take naps after relaxing in the baths.
The bathing area often features many shapes, sizes and depths of bath tubs, some even featuring different mineral or aromatic infusions in the water. Effervescent baths are said to be good for oxygenating the skin and improving circulation. Baths infused with Japanese sake can also be found. Chinese herbs, “kanpou”, are a respected form of medicine in Japan, and can sometimes be found steeping in baths at these traditional onsen. An electric bath, or “denki-buro”, features an electrical current, sometimes pulsating in waves, the contracts stiff, sore muscles in order to release the painful tension; but these baths are not for the faint-hearted and can often be quite intense.
Sometimes there will be a room featuring a “salt-bath”. It is a heated sauna in which guests grab handfuls of salt from a jar and use it to exfoliate the skin. After working up a sweat in the heat, the salt is then washed off before returning to the other baths.
“Onsen” are considered to be the highest quality bath houses. The water from the source of the spring must reach a certain temperature in order for the bath house to be considered an onsen. If the water of the spring falls below this temperature, the bath house is referred to as a “sento”. Both onsen and sento are excellent, relaxing experiences, although onsen are rarer in the largest cities. The spring water is most commonly of two mineral infusions, sulfur or alkali. The sulfur smells slightly of eggs and is considered mildly corrosive, but the content is minimal enough to still be safe for long soaks. Alkali does not have a particular smell, and is often the preferred spring. Regardless of the mineral content, the true value of a hot spring is the way it leaves your skin feeling. The best water softens the skin, making it smooth and slippery, a feeling referred to in Japanese as “nuru-nuru”.
The cheapest bath houses may only require about 300 yen to enter, but the average onsen may cost around 800 to 1200 yen, while some sento in the largest cities in Japan costing upwards of 2000 yen. Towels may be rented for an additional fee.
There is a degree of protocol involved when bathing. No clothes are worn, so guests undress in locker rooms before entering the baths. A small towel is brought along, but it is considered rude to soak the towel in the bath. Many rest the towel on top of their head while soaking in the baths. Before getting in the water, however, you are expected to wash your body in showers near the baths. You’ll often find mirrors with stools in front of them to sit on while you wash. Some bath houses provide soap, shampoo and condition, but older, smaller ones often don’t.
After a nice, long soak, milk or yogurt is often drunk to complete the experience, and you will often find vending machines offering a selection of drinkable dairy. There is usually a wide room covered in tatami mats on which you can lie down and take a nap before leaving the establishment, and some larger, more expensive onsen provide electric massage chairs for their guests.