12 hot springs
Iron springs are rich in iron content. The water is colorless when it first emerges but turns amber as the iron oxidizes upon contact with air. It has long been known as 'the women's bath.'
The iron content is believed to help with mild anemia. It also offers strong heat retention, which may help with cold sensitivity.

Iron(II)-containing - Calcium ( - Magnesium ) - Sodium - Bicarbonate - Chloride Spring

Simple Hot Spring / Simple Sulfur Spring / Acidic - Iron(II) - Sulfate Spring

Acidic - Iron(II) - Sulfate Spring / Iron(II)-containing - Aluminum - Sulfate Spring

含鉄・二酸化炭素-カルシウム-炭酸水素塩泉

Simple Sulfur Spring / Acidic - Iron(II) - Sulfate Spring
Iron(II)-containing - Sodium - Bicarbonate Spring
Acidic - Copper-containing - Iron(II) - Sulfate Spring
単純鉄泉(硫酸塩型)
Iron(II)-containing - Sodium - Bicarbonate - Chloride Spring
Iron(II)-containing - Aluminum - Sulfate Spring
Iron(II)-containing - Calcium ( - Magnesium ) - Bicarbonate Spring
単純鉄(Ⅱ)泉(炭酸水素塩型)
| Name | Prefecture | Water Quality | Source-fed | Onsen Value |
|---|---|---|---|---|
| Koakazawa Hot Spring Rakuyokan | Nagano | Iron(II)-containing - Calcium ( - Magnesium ) - Sodium - Bicarbonate - Chloride Spring | Natural Source Flow | 4 |
| Doroyu hot spring | Akita | Simple Hot Spring, Simple Sulfur Spring, Acidic - Iron(II) - Sulfate Spring | Natural Source Flow | 4 |
| Tsukahara Onsen Kako-no-Izumi | Oita | Acidic - Iron(II) - Sulfate Spring, Iron(II)-containing - Aluminum - Sulfate Spring | Natural Source Flow | 3 |
| Natural Carbonated Hot Spring Nomon-yu | Nagasaki | 含鉄・二酸化炭素-カルシウム-炭酸水素塩泉 | Natural Source Flow | 3 |
| Washikura Onsen Kogen Ryokan | Fukushima | Simple Sulfur Spring, Acidic - Iron(II) - Sulfate Spring | Natural Source Flow | 3 |
| Yawatahama Kuroyu Onsen Minato-yu | Ehime | Iron(II)-containing - Sodium - Bicarbonate Spring | - | 3 |
| Fuigo Onsen | Tokushima | Acidic - Copper-containing - Iron(II) - Sulfate Spring | Natural Source Flow | 3 |
| Aoki Kosen | Yamanashi | 単純鉄泉(硫酸塩型) | - | - |
| Yunoami Onsen Shikanoyu Matsuya | Ibaraki | Iron(II)-containing - Sodium - Bicarbonate - Chloride Spring | Natural Source Flow | - |
| Nuruyu Onsen Ryokan Nikaido | Fukushima | Iron(II)-containing - Aluminum - Sulfate Spring | Natural Source Flow | - |
| Sugatani Onsen | Shiga | Iron(II)-containing - Calcium ( - Magnesium ) - Bicarbonate Spring | Natural Source Flow | - |
| Takarabune Onsen Yumoto Kotobuki | Shiga | 単純鉄(Ⅱ)泉(炭酸水素塩型) | Partial Natural Flow | - |
Q.Why does iron spring water turn amber-colored?
A.The water is colorless when it first emerges, but the iron it contains oxidizes upon contact with air, turning the water amber.
Q.Why is the iron spring called 'the women's bath'?
A.Because the iron content is believed to help with mild anemia, it has long been considered well-suited for women.
Popular hot springs from Hitou Map









