Onsen in Hirayu
In this area is located the highest number of onsen in all Japan (in this case made of sulphureous water). The area surrounding Takayama is called Hirayu (Okuhida). Almost all the onsen are reachable via bus, Nohibus. Heading towards Shinhotaka ropeway. If you are traveling by car all the facilities are accessible. Usually, it takes less than a couple of hours to get there, depending on the season and on the road conditions. The hot springs can be mixed or separate. Tattoos are usually allowed.
What is an onsen?
Hot springs in the "Land of the Rising Sun" are called onsen. Much like in Italy—think of Saturnia or the Balena Bianca—they feature open-air baths known as rotenburo. The water naturally flows from a running spring into pools that are either slightly adapted natural basins or artificial stone structures. The types of thermal waters across Japan vary significantly depending on the location. You can find sulfurous waters, naturally sparkling springs, iron-rich or chlorinated waters with minerals like calcium and magnesium, aluminum, sodium bicarbonate, slightly corrosive waters (not suitable for sensitive skin or children), and even mildly radioactive springs designed to treat rheumatism. There is truly something for every need.
Generally, you will find onsen divided into separate areas for men and women, mixed-gender baths, and private rooms. Following ancient tradition, bathing is done completely naked. However, in mixed-gender outdoor pools, many places nowadays do require a swimsuit. Thoroughly washing your entire body before entering the water is strictly mandatory. If you are inside a structured facility, you use the provided showers; in rural, wild areas, you wash at the edge of the pool using raw thermal water, making sure none of the rinsing water flows back into the bath. Why? Because for the Japanese, water is an element of purification, and everyone does their part to prevent contamination, out of both basic hygiene and mutual respect.
Depending on the location, visitors with tattoos may not be admitted, so I highly recommend checking in advance. In remote areas where the onsen is not part of a private facility, admission is often free, but a small donation is expected to support the locals who maintain and clean the site. In contrast, at hotels and traditional inns, entry fees can range from €5 to over €20, reflecting the premium amenities provided. Onsen cater to every preference, and relaxing in them remains one of my absolute favorite activities.