New Welcity Yugawara - Izumi no Yuニューウェルシティ湯河原 いずみの湯

New Welcity Yugawara sits at the upper end of the valley, technically in Atami City (静岡県熱海市泉107) despite the Yugawara Station address used for GPS navigation. It is a 民間保養施設 - a private welfare resort operated under Meguro Ward - which means Tokyo municipal workers and residents can access it at preferential rates while the general public pays the standard admission. In practice, this produces a specific clientele: '落ち着いた客層、おしゃべりがうるさい学生もおらず' (a calm crowd, no rowdy students) - the kind of quiet that makes a mid-week soak feel genuinely restorative.

The day-use facility is called いずみの湯, and it holds two distinct baths within the outdoor area. The large露天風呂 is Yugawara's biggest by surface area - 40-person capacity, roughly 41°C, open-air with valley views - and is circulation-filtered with chlorination. The石風呂 (stone bath) next to it is the better water: 源泉かけ流し from the same 湯河原温泉混合泉 spring, around 43°C, with a posted notice that the temperature varies by season and ambient air temperature. That last detail is how you identify genuine kakenagashi - no thermostat means no recirculation. Older reviews (2013-2014) noted chlorine in the outdoor bath; more recent visitors report clean water, which may reflect treatment improvements or simply that they spent their time in the stone bath.

Alongside the baths: a sauna running at 82°C with TV monitors inside and a cold water pool adjacent, plus a conventional indoor bath for days when the outdoor area is too exposed. The sauna closes at 22:00, so later arrivals miss it - arrival by 20:00 is the practical cutoff for the full facility. A second-floor free rest area and optional private-room resting (yukata required, ¥300) mean that a half-day here can comfortably stretch to a full one.

Admission is ¥1,100 (tax included) per adult plus the Yugawara 入湯税 of ¥150, with child pricing at ¥550 and toddlers ¥440. Meguro Ward members and certain ward workers can access a discounted rate - one reviewer paid ¥770. Parking is a flat ¥200 regardless of duration. The free shuttle from Yugawara Station runs from the rotary stop near the Doi Sanshiro statue (left side) - check the current schedule with the facility before relying on it. Towel and yukata rentals are available but not included; bring your own towel to keep the total at ¥1,250.

One practical caveat: peak-period surcharges are steep. A GW 2024 visitor paid ¥1,800 base before adding deep-night fees, and rated the value 'コスパが悪すぎる.' The standard-season price is genuinely good for what's on offer; the holiday price is not. Plan accordingly.

In the Yugawara onsen roster, New Welcity fills the scale slot: it is the facility you recommend when someone wants to stretch out, soak long, and not feel pressed for space. For the purest mineral experience, the stone bath inside いずみの湯 is the move. For the broadest variety, Miyakami no Yu in the lower valley has carbonated springs, mud sauna, and herb tent. For the deepest historical atmosphere, Mamanenoyu is a ¥300 toji house less than a kilometre away. New Welcity serves its purpose best when the priority is space, convenience, and a day that doesn't need to end.

住所: 静岡県熱海市泉107 (GPS navigation: 神奈川県足柄下郡湯河原町宮上359)

電話番号: 0465-63-3721

営業時間: Day-use (いずみの湯): 11:00-24:00 (last entry 23:00; sauna closes 22:00) + 5:00-9:00 morning window

タオル: Towel rental available (¥330). Shampoo, conditioner, body soap, and hair dryer provided. Bring your own towel to avoid the rental charge.

浴槽の種類: 石風呂（源泉かけ流し）, 大露天風呂, 内湯, サウナ, 水風呂

源泉: 湯河原温泉（混合泉）

泉質: ナトリウム・カルシウム-塩化物・硫酸塩泉 (弱アルカリ性低張性高温泉)

源泉温度: 63°C

pH: 8.4

温泉の取り扱い: mixed

「湯河原最大級の露天風呂が自慢の宿」

A facility that takes pride in Yugawara's largest outdoor bath.

「源泉かけ流しの石風呂だけは、案内看板に気温でお湯の温度が毎回違う」

The stone source-flow bath alone has a sign that says the temperature varies each time depending on the air temperature.

「湯あたりがよく、湯上り感もさらさらでいいと思います」

The water feels gentle on the body and leaves a smooth, refreshed sensation after bathing.

「落ち着いた客層、おしゃべりがうるさい学生もおらず」

A calm crowd - no rowdy students, no loud chatter.

「広々足も伸ばせて最高です」

Spacious enough to stretch your legs - the best.

「館内全て綺麗でフロントスタッフさんも親切で丁寧」

The whole facility is clean and the front desk staff are kind and attentive.

「コスパが悪すぎる」

The value for money is just too poor.

複数のプラットフォームで収集した情報に矛盾があった箇所です。

• Per-bath water handling (outdoor vs stone bath vs indoor): Three distinct water-treatment tiers within いずみの湯: 石風呂 (stone bath) - 源泉かけ流し, ~43°C, temperature varies with ambient air (no artificial thermostat - this is the clearest signal of genuine kakenagashi behavior); 大露天風呂 (large outdoor) - 循環 + 塩素消毒, ~41°C (chlorine noted in 2013-2014 reviews; 2022-2023 reviewers report no odor - possible treatment upgrade or just a reviewer preference for the stone bath); 内湯 - 加温・循環濾過・微塩素. Rubric §7.17 applies: always specify per-bath, never inherit the stone bath's kakenagashi status to the whole complex.
• Address and GPS navigation: Official address is 静岡県熱海市泉107 - the facility is on the Shizuoka side of the Kanagawa/Shizuoka border. Navigation systems often fail to route correctly from this address for drivers approaching from the Kanagawa side. The official site recommends using 神奈川県足柄下郡湯河原町宮上359 for car navigation. Map URL in this guide uses coordinates (35.142244, 139.081020) sourced from the Meguro Ward facility page.
• Map URL - corrected from prior copy-paste bug: The guide entry previously used maps.app.goo.gl/FHrPeYpeksGSfzmF6 for this facility. That link resolves to 福浦漁港 みなと食堂 (Fukuura Minato Shokudō), a completely different facility on the Yugawara coast. Corrected to coordinates-based URL (35.142244, 139.081020). The Fukuura Shokudō entry retains FHrPeYpeksGSfzmF6 because that link is correct for the restaurant.
• Peak surcharges and value variance: Standard season admission is ¥1,100 (tax incl.) per adult + ¥150 入湯税. During GW, Obon, year-end/New Year, and other peak periods, base admission can rise to ¥1,800 or higher with additional late-night or deep-night fees on top. One GW 2024 reviewer found the value poor at that price. Surugabank's older pricing (¥1,000/¥500/¥300) is stale and should not be published.
• '万葉の湯' disambiguation: Three distinct uses of '万葉の湯' in the Yugawara context: (1) New Welcity's in-house bath named '万葉の湯' - for lodging guests only, circulated; (2) the rotating women's bath name inside Kogome no Yu (alternates with '小梅の湯'); (3) the 万葉倶楽部 chain (はだの, 町田, 沼津, etc.) that transports Yugawara spring water to out-of-town facilities and brands it '湯河原温泉 万葉の湯.' Note: there is NO standalone 万葉の湯 day-use facility located in Yugawara town. The 万葉倶楽部 chain's spring source (湯河原 第183号) is in Yugawara but the facilities are elsewhere.
• Meguro Ward welfare facility - membership pricing: New Welcity is a 民間保養施設 contracted under Meguro Ward (目黒区). Meguro Ward residents, commuters, and their accompanying family members can access preferential pricing - one Nifty reviewer cited ¥770 with a member discount. General visitors pay standard admission. The guide targets general visitors; member pricing is noted as a data point but not the lead.

• ニューウェルシティ湯河原 公式サイト（日帰り温泉）
• Niftyonsen - ニューウェルシティ湯河原 いずみの湯
• Surugabank 井伊部長の温泉グルメ探訪
• ゆこゆこ お風呂・温泉情報
• 湯河原温泉 公式観光サイト - いずみの湯
• 目黒区 民間保養施設案内