Looking into Hotel Oonoya

I've been digging into inns and campsites that look easy to reach without a car, and it's turned into a bit of a series.

This time I looked into Hotel Oonoya, a hot spring hotel in Atami. While I was planning a camping trip, I started thinking, “Maybe just relaxing at a hotel today wouldn't be so bad.” This place caught my eye as somewhere that seems easy to enjoy even for an indoor type like me.

The Short Version

With a Roman bath that holds 300 people and an open-air bath overlooking Sagami Bay, plus meals and in-house play spaces, my impression was of a hot spring hotel where you could seemingly spend the whole day without leaving the property.
As for Rakuten Mobile signal, the official tool rated it “C”. If you're counting on mobile data, it might be a good idea to check ahead of time.

I've put the details below.

A Seaside Hot Spring Hotel in Atami with a Roman Bath for 300 People

Hotel Oonoya is a hot spring hotel on the coast in Atami, Shizuoka Prefecture, and apparently it's run by Itoen Hotels. It doesn't seem to have its own standalone website; instead, there's a dedicated page within the operator's site.
You can find the official page here.

The hotel sits right in front of Sagami Bay, and it's described as having easy access to Atami Port and the entertainment district. A sea fishing facility and a waterfront park are apparently within a 10-minute walk of the hotel.

Basic Info to Know First, from Check-in to Booking

Check-in/check-out: Check-in seems to be from 3:00 PM, and check-out is by 11:00 AM. The official site had a notice saying that for stays from July 18, 2026 through August 29, 2026, check-out changes to 10:00 AM. It may also differ depending on the plan.
Booking: Besides the vacancy search and online booking on the official site, apparently you can also book by phone.
Price: I couldn't find specific prices in the main text of the official site. There seems to be a note saying that booking through the official site is the cheapest.
Parking: There's space for about 100 cars, and it's free for guests, apparently. You can use it from 12:00 PM until 11:00 AM on the check-out day. When it's busy, cars get parked in tandem, and you may be asked to leave your key.
Pets: Listed as not allowed.
Day-use bathing: In my research, I couldn't confirm whether it's offered or how much it costs.

Komorin

I couldn't find the prices in the main text of the official site, so if you're curious, the quickest way is probably to enter your dates in the vacancy search and see.

From the Roman Bath to Private Baths, There Are Apparently 10 Hot Spring Facilities

According to the official site, there are 10 hot spring facilities in total inside the hotel. The main public bath, the Roman bath, holds 300 people, and there's also an open-air bath overlooking Sagami Bay.
There's a private bath you can use 24 hours a day, and apparently there are 6 types of family baths.

The water is a calcium-sodium chloride spring (hypertonic, neutral), and I also saw a mention that the hotel has its own source. If you choose an inn mainly for the baths, that sounds like a big draw.

Buffet, All-You-Can-Drink, and In-House Facilities Caught My Eye Too

Meals seem to be a buffet with Japanese, Western, and Chinese dishes. The official site mentions about 80 dishes and about 30 drinks. A booking site's description said “about 70 types,” so the numbers vary a bit.
I also saw a note that all-you-can-drink, alcohol included, at dinner is covered by the room rate.

Inside the hotel there's karaoke, table tennis, billiards, and mahjong, all free, apparently. Only mahjong seems to require a reservation in advance.
Rooms include Japanese-style and Japanese-Western rooms, plus a higher-grade Takasago-kan. From the upper floors, you can apparently see the sea and the Atami Sea Fireworks Festival. It looks like you could spend a whole day without ever leaving the hotel, and as an indoor type, the facilities really appealed to me.

Can You Get There Without a Car? Checking Access from Atami Station

I'm a paper driver, so how to get there from the station matters a lot to me. The official access page says it's about 30 minutes on foot from Atami Station, or about 10 minutes by bus. However, from the official site alone, I couldn't tell whether that bus is a shuttle bus or a regular route bus.

Shuttle bus: From Atami Station, it runs every 30 minutes from 13:50 to 17:20 (13:50, 14:20, 14:50, 15:20, 15:50, 16:20, 16:50, 17:20).
Shuttle bus from the hotel: Every 30 minutes from 8:50 to 11:20 (8:50, 9:20, 9:50, 10:20, 10:50, 11:20). Apparently the times can change depending on conditions.
Boarding point: The official site is said to have it in a PDF guide, but I couldn't confirm the location from the main text this time.
Route bus: According to a booking site, you board at Atami Station's Bus Stop No. 7 and get off at Marine Spa Atami.
Fare: I saw a different booking site saying the shuttle bus is free. But I couldn't confirm any fare information on the official access page.
Direct bus from Ikebukuro: Apparently there's a round-trip bus connecting Ikebukuro Station and the hotel. It costs ¥3,850 round trip or ¥1,925 one way (tax included), and a phone reservation at least 2 days before your stay is required.

It seemed to me that the shuttle times are concentrated in the afternoon from the station and in the morning from the hotel. You'll want to check ahead whether they fit your arrival and departure times.

Rakuten Mobile Signal Conditions

I used the official “my Area Connectivity Simulation” to check the location of Hotel Oonoya in the Wadahama-minamicho area of Atami (checked on October 6, 2026). The overall rating came up as “C”.

If you plan to use data a lot during your stay, it's probably a good idea to check beforehand. The baths and meals seem to be all in-house, but if you'll be streaming videos or working remotely, it might be something to keep in mind. Also, I couldn't find any information about the hotel's Wi-Fi in my research this time.
If you're curious about the signal, try checking your own destination with Rakuten Mobile's official simulation tool.

Komorin

The rating was C. I think it's best not to count on the signal here and just treat it as a place to unwind with hot springs and a buffet.

See Rakuten Mobile Details

Wrapping Up

To sum up, my impression of Hotel Oonoya is that it's a hot spring hotel in Atami built around a Roman bath for 300 people and an open-air bath overlooking Sagami Bay, with a buffet and free-to-use in-house facilities as well, where you could seemingly spend the whole day without leaving the property.

Hot springs: There are 10 inside the hotel, and apparently the private bath can be used 24 hours a day.
Meals: A Japanese, Western, and Chinese buffet, with all-you-can-drink at dinner included in the room rate.
Access: There seems to be a shuttle bus from Atami Station, but I couldn't confirm the boarding point or fare from the main text of the official site. It's probably safer to check the times in advance.
Signal: The rating from Rakuten Mobile's official tool was “C”. If you use data a lot, it's a good idea to check ahead.

I couldn't confirm things like room rates or whether day-use bathing is offered this time, so if you're interested, please check the official site.

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