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Seizan Yamato

青山やまとあおやまやまと

Lodging
Chubu·Shizuoka

Day Use

Yes
14:00–21:30

Bathing & Water

Natural onsen water

Uses natural hot spring water

Outdoor BathYes

Open-air outdoor bath

Indoor BathYes

Enclosed indoor bathing area

SaunaYes

Dry heat sauna room

Cold BathNo

Cold water plunge bath, typically used after sauna

Capabilities

Private BathYes

Private bath available for day-use visitors or hotel guests to reserve

Private cypress bath "Suzume no Yu" is normally 1,650 yen for a 50-minute reserved slot; complimentary as an official-website booking perk.

Room OnsenYes

Private onsen bath in guest rooms, for overnight guests only

Mixed BathingNo

Shared bathing area for all genders

Policies & Services

TattooWith Conditions

Allows entry with visible tattoos

Tattoos (including fashion tattoos) are not permitted in the large communal bath or outdoor bath; private/room baths remain available.

KidsWith Conditions

Welcomes children and families

A child may bathe in the opposite-gender large communal bath with a guardian only up to age 6.

Rest AreaYes

Relaxation space for after bathing

ParkingYes

On-site or nearby parking available

Water treatment

Treated and recirculated
from Article 18 disclosure
  • Added water
    Yes
  • Reheated
    No
  • Recirculated
    No
  • Disinfected
    Yes
    塩素系薬剤
  • Bath additives
    No

岡173号・鎌田41号・岡277号 地下貯湯槽混合泉

Oka No. 173 / Kamata No. 41 / Oka No. 277 Underground Storage-Tank Blend

Operated by · 青山やまと

Mixed source

Simple
Hot source · 51°C
Known good for
  • Aches & jointsstiff shoulders
  • Smooth skindry, rough skin
  • Recoveryfatigue, stress

A blended simple thermal water drawn from three Ito Onsen wells (Oka No. 173, Kamata No. 41, Oka No. 277) and mixed in an underground storage tank before being sent to the baths. Total dissolved solids sit at 696 mg/kg with a pH of 8.2 — weakly alkaline, gentle on the skin, and squarely in simple-spring territory. The wellhead is hot at 51 degrees Celsius and the water is cooled to the bathing range of 39 to 42 degrees before serving.

Sampled at mixing tank·Analyzed Oct 17, 2019·株式会社サイエンス

Explore the water

Views

Sea
Mountains
City

About

Seizan Yamato sits on a quiet hillside above Ito, with a large indoor and outdoor bath complex filled with kakenagashi (掛け流し) spring water that's soft on the skin. One of the baths, Tsuki no Yu (月の湯, "moon bath"), looks out over the town and Sagami Bay; men and women use it at different times of day. There's a sauna but no cold plunge. A private cypress bath, Suzume no Yu (すずめの湯), is normally a paid reservation but comes free as an official-site booking perk, and some of the higher-grade rooms have their own kakenagashi open-air tub on the balcony. It runs like a big, full-service ryokan rather than a small inn: staff carry the luggage, tea is brought to the room on arrival, dinner is served course by course in private dining rooms, and the futons are laid out fresh each night. Guests describe it as a classic ryokan stay with a bit more structure than the rustic version.

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Reserve or check availability on a booking site.

SM
Sergey M
1 year ago

240. Seizan Yamato, Ito Stayed overnight with dinner and breakfast. Large ryokan, lots of guests, mostly Japanese, English is limited. In the evening there was a live performance somewhere in the ryokan (didn't look into the details since it's not my thing). For the kaiseki dinner you can choose the main dish from four options — in my case I could pick two since it was a double kaiseki, and they honestly bring both. In the area closer to the baths, before the changing rooms, there were various jugs of water and tea. 1. Private wooden bath, can be reserved for 1650. Couldn't find a proper water composition sign, only a sanitary one. Clear water, temperature 43–44, good air, nice window design. 2. First bath set (M/F rotation). 2.1. Indoor bath. Air quality inside is okay, but there's a slightly foul water smell in the shower area (not from the onsen, but from the shower drain). The city view through the glass disappears once you sink into the water. Clear water, temperature 40. 2.2. Outdoor bath with clear water, temperature 42. There's a window with a city view, but the view disappears when you sink in. 2.3. Sauna. 3. Second bath set (M/F rotation). Online photos of the baths match. 3.1. Indoor bath with clear water. Temperature 42. Comfortable to breathe inside. 3.2. Outdoor stone bath. Cozy onsen but no view. Clear water, temperature 40–41. 3.3. Sauna. Solid place, good service, tasty and interesting food. No major issues and everything's fine, but can't say it left a lasting impression.

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Last updated July 16, 2026