Matsushiro Onsen is a hot spring area in the Matsushiro district of Nagano City, Nagano Prefecture. It was once known as Kagai Onsen, and today it is enjoyed by visitors as a peaceful hot spring destination surrounded by the historic atmosphere of Matsushiro.
One of the main accommodations in the area is Mercure Nagano Matsushiro Resort & Spa, formerly known as Shinshu Matsushiro Royal Hotel. Opened in 1996, the hotel has a distinctive character, functioning more like a city hotel on weekdays and taking on a resort-hotel atmosphere on weekends and holidays.
Other accommodations include traditional hot spring inns such as Matsushiro-so, where guests can enjoy the distinctive golden-colored waters. Ichiyokan, which preserves the historic name of Kagai Onsen, also welcomes visitors for day-use bathing, offering another way to experience the area’s long hot spring tradition.
Visitors who simply want to enjoy the hot springs without staying overnight can find several options in and around the Matsushiro Onsen area.
Matsushiro Onsen Community Center is located at 151-2 Matsushiro Onsen, Nagano City.
Ichiyokan, located at 55 Tojo, Matsushiro-machi, Nagano City, is a historic inn that continues the tradition of Kagai Onsen.
Some round-trip bus tickets to the Matsushiro Onsen area also include a day-use bathing ticket, making it convenient to visit from Nagano Station.
Matsushiro’s hot springs have a history surrounded by fascinating stories. It is said that the Buddhist priest Nichiren bathed here during the Kamakura period. There is also a tradition that the powerful Sengoku warlord Takeda Shingen used the springs as one of his secret bathing sites.
In 1766, during the administration of the Matsushiro Domain, local village leaders petitioned for the development of the hot spring facilities. Members of the Sanada family are also said to have visited the springs for therapeutic bathing.
In 1805, residents of Kagai Village formally applied to establish the area as Kagai Onsen. The history of the spring reflects the strong connection between the local community and its treasured hot spring resources.
The hot spring later went into decline, but it was revived in 1822. Much later, a series of earthquake swarms beginning in 1965 caused groundwater to emerge and increased the amount of hot spring water available. This geological history adds another fascinating dimension to Matsushiro’s hot springs.
The main source currently supporting Matsushiro Onsen is Shin No. 3 Spring, whose water is piped from the western foothills of Mount Amikam. A survey conducted in 2008 recorded a spring temperature of 45.2°C and a pH of 6.7, classifying the water as a neutral, high-temperature, highly concentrated mineral spring.
The water contains a relatively high level of carbon dioxide, producing a subtle sparkling sensation in the bath. Its distinctive characteristics also include a pronounced salty taste and an iron-rich quality.
The water emerging from the spring is colorless and transparent. However, once it fills a bath, rust-colored mineral deposits can gradually form on the walls and surfaces of the tub.
These deposits are caused by the oxidation and precipitation of iron ions. The resulting brown coloration is one of the features that gives Matsushiro Onsen its distinctive and atmospheric appearance.
The Matsushiro area has several other sources, including Kagai Onsen No. 1, No. 2 and No. 3 Springs, as well as Matsushiro Onsen Shin No. 1 and former No. 1 Springs. Each source has its own water characteristics and uses.
In particular, Kagai Onsen No. 1 Spring is a self-flowing spring, allowing visitors to experience a more traditional image of naturally emerging hot spring water.
Travelers looking for spacious bathing facilities and a resort-style stay can choose Mercure Nagano Matsushiro Resort & Spa. Those who prefer a quieter experience surrounded by local history can stay at traditional accommodations such as Matsushiro-so or visit Ichiyokan.
One of the greatest attractions of Matsushiro Onsen is its proximity to the historic castle-town area of Matsushiro. Visitors can easily combine a relaxing hot spring bath with sightseeing among traditional streets and historic landmarks such as Matsushiro Castle, the Sanada Residence, and the Zozan Memorial Museum.
Convenient bus connections from Nagano Station also make Matsushiro Onsen an accessible destination for travelers exploring northern Nagano.
Matsushiro Onsen offers more than a relaxing bath. Its long history, traditional bathing culture, distinctive mineral deposits, and fascinating geological background create a unique experience in which history and nature come together.
From legends associated with the Kamakura and Sengoku periods to the development of the hot spring under the Matsushiro Domain, the area has been closely connected with the people who lived here for centuries. The unusual brown mineral deposits that appear in the baths provide an especially memorable glimpse into the chemistry of the spring water.
With its convenient location near the historic sights of Matsushiro, Matsushiro Onsen is an excellent addition to a trip around Nagano City and the Zenkoji area. A visit offers the chance to slow down, enjoy the distinctive waters, and experience the atmosphere of a historic town where hot springs, culture, and nature meet.