Onsens are natural hot springs and a major part of Japanese culture. The word can be used to reference individual hot springs, a group of them, or a resort town dedicated solely to hot springs. Some onsens come as part of a ryokan (a Japanese inn) in which visitors can only use the onsen if they’re staying for at least a night, but there are some ryokans that allow daytime visits. But whatever the kind of onsen, Japan’s got them all in spades.

The mineral-rich waters have a variety of benefits, including softening skin, relieving fatigue, alleviating aches and pains, and aiding bodily functions. Before entering a hot spring, you’ll have to clean yourself with water and soap that the staff will have set up beforehand, and then you’ll enter the waters completely nude — but worry not: the areas are separated by gender. You’ll be able to find an onsen or onsen town in every region of Japan, but here are seven of the coolest ones that you should definitely seek out.

1. Nishiyama Onsen Keiunkan — Hayakawa, Yamanashi Prefecture

With over 1,300 years of history, the Nishiyama Onsen Keiunkan has been recognized by the Guinness World Records as the oldest hotel in the world. It was founded in 705 AD by Fujiwara Mahito and has been owned and operated by the same family for over 50 generations ever since. It’s catered to famed figures in Japanese history, including samurai and shogun. The tranquil hot-spring hotel is located at the base of the Akaishi Mountains, and its waters are sourced from four different hot springs around the Fossa Magna, whose properties of sodium, calcium nitrates, and chloride are said to have the effects of relief on gastrointestinal disorders, muscle pain, constipation, and healthy skin.

There are a total of six baths, four are open-air baths and two are indoors (and two of those are private in case you want some alone time). All have incredible views of the surrounding nature and waters that are sure to heal your body from the day’s exertion. There are over 30 rooms for guests all designed in traditional Japanese fashion, but some of the more luxurious rooms come with larger balconies and private baths. A stay will also grant you a few prepared meals per day, called “Mountain Kaiseki Banquet,” where you’ll have hot and cold dishes made with fresh, high-quality ingredients. Rooms start at 37,000 yen ($300) a night, but picture yourself soaking in the hot spring, and you’ll be pulling out your wallet before you know it.

2. Hotel Mifujien — Lake Kawaguchiko, Yamanashi Prefecture

The only thing better than a room with a view is one with an onsen. Hotel Mifujien is located along Lake Kawaguchiko in the Fuji Five Lake region, and Kawaguchiko is known for its awe-inspiring views of revered Mount Fuji. In addition to having an onsen, with both an open-air and indoor bath, Mifujien is also a ryokan, and while most ryokans require visitors to have a reservation to stay at least one night before they’re able to use any of the facilities, Mifujien is one of the only ones in the area that accepts day visitors. A day visit will cost around 1200 yen (about $10). But if you’re planning on staying the night, there are 46 Japanese-style rooms and three western-style rooms. Costs start at 14,000 yen ($125). Whatever you decide, every room will grant you a perfect shot of Fuji.

3. Notoya Ryokan — Ginzan Onsen, Yamagata Prefecture

Ginzan Onsen is a hot-spring town, and its name translates to “silver mountain hot spring.” The town is made up of mostly onsens and ryokans that line its streets, making for a nostalgic scene or something straight out of a Studio Ghibli film. Most of the buildings are three or four stories, with exposed woodwork and white walls, and the Ginza Kawa River runs right through it with bridges linking each side of the pedestrian-only streets. It’s hard to pick just one place, but we recommend Notoya Ryokan. Located in the middle of Ginzan, it’s the focal point where all eyes will be drawn. Tall and strikingly beautiful, Notoya is designed in the Taishō-era style, and the building itself has a history that goes back over 500 years to the days when Ginzan was just a silver mine. The vintage inn has an open-air onsen, a public bath, cave bath, private bath, and 15 guest rooms each equipped with a private bathroom. Rooms start at 15,000 yen ($134) a night.

4. Dai-ichi Takimotokan — Noboribetsu, Hokkaido

All the way up on Hokkaido, Noboribetsu is the northernmost island’s most famous hot-spring resort town. Hokkaido is known for its gorgeous scenery, so you really can’t go wrong with any time you choose to visit. That said, visiting during winter when everything’s touched by layers of snow or autumn to see colorful fall foliage can’t hurt. Just above Noboribetsu is Jigokudani, otherwise known as “Hell Valley,” a valley with volcanic activity, hot steam vents, and streams with sulfur. Most of the onsens get their water from Jigokudani, so the sulfur and hydrogen sulfide in the hot springs have properties that will soften skin, and their iron content will do wonders for any fatigue.

Dai-ichi Takimotokan, which has been in business for more than 150 years, is one of the more well-known onsens in town, and the interior is a mix of both traditional and modern styles. The spacious inn has 35 baths alone, sourced from seven different hot springs. Entertainment activities include karaoke; a video arcade; and strategy board games like Go, Shogi, and Mahjong. Overnight rates start at 11,000 yen ($98) per person per night, but there’s daytime admission here, as well, for around 2,000 yen ($17) and 1,500 ($13) after 4:00 PM.

5. Takegawara Spa — Beppu, Ōita Prefecture

Beppu is another city famous for its hot springs, and it’s divided up into eight different springs. Altogether, they produce more volumes of water than any other onsen areas in Japan. Takegawara is the top onsen in Beppu and was built in 1879. Besides baths whose waters are rich in minerals like sodium hydrogen, calcium, and magnesium chloride, it also offers sand baths where attendants will, essentially, bury you in sand. You’ll be wearing a yukata (a summer Japanese robe) when you lay down in a hole that’s been dug out for you, and then hot black sand is poured on top to cover you completely. For 10 minutes, you get the feeling of being buried alive, but the relaxing qualities of the hot sand should melt away any anxieties you might have about that. No overnight stays here, and daytime visit prices depend on what kind of bath you’d want. A regular soak in a hot spring is 100 yen ($0.90) while a sand bath is 1,030 yen ($9).

6. Tosen Goshobo — Arima Onsen, Hyōgo Prefecture

Arima Onsen is known as one of Japan’s Three Ancient Springs, a group of the most ancient and famous hot springs in the country. According to the Chronicles of Japan, the second-oldest book of classical Japanese history, Arima goes back over 1,300 years to the time of the gods when two Shinto deities saw injured cows being cured of their ailments after they soaked in the waters. There are three types of hot springs in Arima, and the kinsen (“golden hot spring) is the most famous. The waters are a golden clay color and are at a controlled temperature of 104 degrees Fahrenheit (though it’s originally double that number).

Tosen Goshobo is one of the oldest ryokans in the area, built around the 12th century, and has since been frequented by famous Japanese literary figures, such as Junichiro Tanizaki and Akiko Yosano, who have also written about the inn in their works. The history is obvious through the wooden architecture and antique design, and while each room is decorated with similar themes, they’re all unique in their own way. Each guest room has tatami mats, shoji screens, and futons, but there are modern amenities like minibars and flat-screen TVs. Goshobo boasts an aromatherapy salon where visitors can treat themselves to massages, facials, and oil treatments, but what you’ll really want to head straight toward is the half open-air hot spring with the mythical golden waters. The wall separating genders even lowers down in one part of the area, allowing people to converse if they want to. Staying the night starts at 20,000 yen ($179) per person, but a daytime visit is only 1,650 yen ($14). It’s closed on weekends and holidays, so be sure to visit during the week.

7. Kokuya Onsen — Shibu Onsen, Nagano Prefecture

Shibu Onsen is another hot-spring resort town, but its proximity to Jigokudani Yaen-koen (Monkey Park) is what makes it really stand out amongst its competitors. As the name Monkey Park suggests, it’s where wild snow monkeys roam about in the natural environment, and visitors can take tours to learn more about the animals, watch them in their habitat, or even see them bathe in natural pools around the area. The 400-year-old Kokuya Onsen is one of the many ryokans that you can stay in, offering six different hot springs, eight baths, and 10 guest rooms with open-air baths. It’s located on Shibu Onsen’s spa street where it’s not uncommon to find people dressed in kimonos and yukatas walking about. For an interesting treat, try Kokuya’s onsen-tamago, a half-boiled egg that’s cooked in hot-spring water. Use of the facilities are for guests only, and prices start at 17,000 yen ($152).