Toshimaen Niwanoyu: Admission, Swimwear Rules & Access

A complete guide to Toshimaen Niwanoyu — covering admission fees, swimwear rules, and how to get there. Just 14 minutes from Ikebukuro and 20 minutes from Shinjuku, this urban day-trip onsen sits right next to the Tokyo Harry Potter Studio Tour, making it a popular post-visit combo.

Toshimaen Niwanoyu Basic Info (Hours, Admission, Directions)

For a day-trip onsen experience in central Tokyo, Toshimaen Niwanoyu is our top pick.

Located right next to Warner Bros. Studio Tour Tokyo (Tokyo Harry Potter Studio), it's a popular way to wrap up a day at the Harry Potter Studio with a relaxing soak at the onsen.

This guide covers everything from facility highlights and admission fees to swimwear rules, directions, and a combo day course with the Harry Potter Studio.

Hours

• Operating Hours: 10:00–23:00 (last entry 22:00)
• Closed: Temporary closures for maintenance (no regular holidays)

⚠️ Temporary closure dates may change without notice. Always check the official website before visiting.

Admission Fees

※ Special days: Golden Week, Obon, year-end/New Year, etc.

※ Admission includes house wear, towel, and bath towel rental. No need to bring your own.

※ A price increase is planned from April 1, 2026. We'll update this guide once new rates are announced!

Bedrock Bath (Additional Fee)

Reservations

No advance reservation required — walk-ins welcome. On weekends and holidays, entry may be restricted during peak hours, so an early visit is recommended.

How to Get There

Use the same Toshimaen Station as the Tokyo Harry Potter Studio.

• Seibu Line Toshimaen Station → 2-minute walk
• Oedo Line Toshimaen Station Exit A2 → 3-minute walk

⚠️ No parking available. Please use public transportation.

Before You Enter — Must Read

⛔ No entry for children under 13. This applies regardless of whether accompanied by an adult.

⛔ Absolutely no entry with tattoos (including stickers). If discovered after entry, you will be asked to leave immediately with no refund.

⭕️ Amenities

Hairdryers and shower heads are ReFa premium models. Women's skincare is by Yukishirosei, and shampoo/body wash is by POLA's top-tier IUGEN line. You can come completely empty-handed.

Toshimaen Niwanoyu Facility Overview

This is an adults-only spa where you can enjoy natural hot springs while overlooking a 3,900㎡ Japanese garden designed by Kenzo Ogata. The natural hot spring, drawn from 1,445m underground (iodine-containing sodium chloride strong salt spring), leaves a salt mineral layer on your skin after bathing that helps retain warmth. It's also famous as a sauna facility ranked 5th nationally in the 2026 Nifty Onsen National Sauna Rankings.

🛁 Hot Spring Zone

Enjoy natural hot springs drawn from 1,445m underground (iodine-containing sodium chloride strong salt spring) while overlooking the Japanese garden. The salt minerals coat your skin after bathing, keeping you warm.

• Open-air rock bath (natural hot spring)
• Open-air Shigaraki-yaki bathtub
• Softened carbonated spring (artificial)
• Indoor natural hot spring bath

🔥 Sauna Zone

Six types of saunas plus dedicated relaxation (totonoï) spaces.

• Thermarium sauna
• Finnish sauna cabin (auto-löyly with natural aromatic wood)
• Tent sauna (group rental available)
• Outdoor Finnish sauna

✔️ Starting April 1, 2026, the women's sauna will be renovated and reopened with a new Nordic birch forest-themed sauna.

🏊 Bade Pool Zone

A co-ed swimwear zone kept at body temperature (~35°C). Designed for health and conditioning through aqua massage using water pressure and currents.

• Bade pool (swimwear required / rental ¥500)
• Steam sauna
• Healing bath
• Outdoor jacuzzi (natural hot spring & softened water)

✔️ The outdoor jacuzzi and Finnish sauna are set in an open space surrounded by the Japanese garden. You can enjoy the garden's changing scenery with every season.

🍽️ Restaurant Ryokusuitei (緑水亭)

Located on the 2nd floor, you can dine while overlooking the garden.

• Ankake Moyashi Chinese Soba ¥930 (most popular post-sauna dish)
• Spice Curry ¥930
• Maguro Don ¥1,800
• Soft Serve Ice Cream ¥390

Toshimaen Niwanoyu How to Use & Important Rules

🚪 How to Use (Steps 1–6)

Here's a step-by-step guide from entry to exit so first-time visitors won't get confused.

Step 1. Shoe Locker

Remove your shoes at the entrance and store them in a shoe locker. Insert a 100-yen coin to lock it and keep the key. The 100 yen is returned when you open the locker upon leaving. Bring a 100-yen coin with you.

Step 2. Front Desk Check-in

Present your shoe locker key at the front desk and pay the admission fee. If you didn't bring a swimsuit, you can rent one for ¥500 at this step.

Step 3. Receive Entry Kit

After payment, you'll receive a locker key, in-house bag, house wear, bath towel, and hand towel.

💡 Inside the facility, you can pay for meals and shopping just by showing your locker key. No need to carry cash. Be careful not to lose the key.

Step 4. Change & Bathe

Change in the locker room and freely enjoy the hot springs and facilities.

⚠️ Swimwear is mandatory when using the Bade Pool (co-ed zone).

Step 5. Settlement Before Leaving

Return your locker key, in-house bag, house wear, towels, and swimsuit (if rented) at the front desk and settle all charges at once.

💡 Restaurant and relaxation service charges are also settled at this step. Check your receipt before leaving.

Step 6. Exit

Receive your shoe locker key back at the front desk and retrieve your shoes. The 100-yen deposit is returned when you open the locker.

⚠️ Rules by Zone

🟠 Hot Spring Zone

• Shower thoroughly before entering the bath
• No swimwear or towels in the bath
• No washing body or hair inside the tub
• Do not dip towels or hair into the bath water
• Dry off before returning to the changing room

🟠 Bade Pool Zone

• Swimwear required (rental ¥500)
• No swimming or diving
• No running or jumping on the poolside
• No physical contact or loud conversation with others

🟠 Relaxation Zone

• No reserving seats with belongings
• Keep conversations to a minimum in quiet areas

⛔ Camera & Phone Usage

Day Trip Combo with Harry Potter Studio

Toshimaen Niwanoyu and the Tokyo Harry Potter Studio are both walkable from the same station, making it easy to enjoy both in a single day.

✔️ After 18:00, Night Spa rates apply — cheaper than regular admission. The route from the Harry Potter Studio connects naturally.

📌 For Harry Potter Studio details (reservations, tickets, highlights), check the guides below.

👉 Tokyo Harry Potter Studio Complete Guide | Highlights, Goods & Directions

Toshimaen Niwanoyu includes towels and house wear with admission, so you can visit completely empty-handed. Just bring a swimsuit and you'll have access to the entire facility, including the co-ed Bade pool.

Since it shares the same route as the Harry Potter Studio, adding it to your Tokyo itinerary is a great way to round out a full day.

🧡 More Helpful Tokyo Travel Guides

👉 Tokyo Harry Potter Studio Complete Guide | Highlights, Goods & Directions

👉 Tokyo Harry Potter Studio Tickets — Booking, Types, Cancellation & Changes

👉 Shinjuku Station Luggage Storage Complete Guide

👉 Japan eSIM Complete Guide