Most advice on choosing a ryokan is a list of nice ones. That is not choosing; that is browsing. The decision actually turns on four variables, and if you get them right almost any well-run inn will work — while getting them wrong will spoil a stay at the best address in Japan.
The question people usually type is how to choose a ryokan, and the honest answer is that the best ryokan in Japan for an anniversary is not a place — it is a configuration. This guide sets out those four, shows how to read them off a listing, and then works through one inn in Izu in enough detail that you can see the method applied.
A hotel sells you a room and leaves the rest to you. A ryokan sells you a block of time — arrival, bath, dinner, sleep, bath, breakfast, departure — with the sequence largely fixed and the staff moving through it with you.
That is the whole difference, and it explains why the usual hotel criteria mislead. Square metres matter less than whether your dinner is served where other people can hear it. A famous name matters less than whether the bath you want is bookable at the hour you will want it. And the single biggest determinant of how the evening feels — the meal arrangement — is often not stated on the booking page at all.
So the question is not "which ryokan is best" but "which of the four variables do I care about, and does this one deliver them."
There is a second reason the hotel criteria fail. In a ryokan the staff enter your room — to lay the futon while you are at dinner, to bring tea on arrival, sometimes to serve the meal itself. A guest who wants to be left alone should be booking a room with its own bath and a private dining room, not a bigger room. The variable that produces solitude is the arrangement, not the square metres.
1. Where you eat. There are three arrangements and they produce entirely different evenings. Heya-shoku, served in your room, is the most private and the most logistically demanding for the inn. A private dining room gives you the same privacy with a proper table. A shared hall, however good the food, is a restaurant. Ryokan often offer different arrangements at different rates, and the difference is rarely visible in the photographs.
A note on the vocabulary, since the listings use it untranslated. Kaiseki is the multi-course dinner, and at a ryokan it is normally included in the room rate rather than ordered — which is why the rate looks high and why skipping dinner rarely saves money. Nakai is the room attendant assigned to you, and at smaller inns the same person handles arrival, dinner and the futon.
2. Which bath you get. A room with its own open-air bath is one thing; a bookable private bath shared among guests is another; a public bath only is a third. The middle option is the one people misjudge — it is normally charged, often in fixed slots, and normally needs booking. If a private soak matters to you, this is the field to check first.
A related point that catches people out: the dinner sitting may be assigned rather than chosen, and an inn will often ask for a preference only if you raise it. If you want to eat late, say so when you book — not on arrival, by which time the kitchen's evening is already laid out.
3. The shape of the day. Check-in and check-out times determine how much of the inn you actually use. An inn taking you at 15:00 and releasing you at 10:00 gives you nineteen hours; one that checks out at noon gives you twenty-one, and that two-hour difference is a morning bath and an unhurried breakfast rather than a scramble.
4. Scale. Ten rooms and sixty rooms are different products. Small inns give personal service and less choice; larger ones give facilities and anonymity. Neither is better, but the mismatch between what you booked and what you wanted is almost always a scale mismatch.
The variable to reason about is not room count on its own but what the count implies for staffing: how many guests one person is looking after on the evening you are there. That is not published, but the room count is a proxy for it, and asking how dinner is served will tell you more than any photograph.
Japanese ryokan sites and the international listing services put the useful information in different places, and neither foregrounds it.
On a Japanese site, look for the onsen page rather than the rooms page: that is where bath types, charges, time slots and booking deadlines are set out. On an English listing, look for the data block near the foot of the page — total rooms, check-in and check-out, whether in-room dining is available, dinner and breakfast start times. Those fields answer three of the four variables in one screen.
One field deserves particular attention: the meal times. An inn serving dinner from 18:00 and breakfast from 07:00 is running a tight schedule and expects you inside it. One offering a two-hour window for each is telling you something about how much it will bend. This is the closest thing to a published measure of flexibility that ryokan give you.
Two fields are worth reading literally rather than generously. "Private open-air bath" and "river view" both cover a wide range on a listing, and neither phrase tells you what you will actually see from the water. Neither is dishonest; both are written by someone who has seen the room and assumes you have too. Photographs on the inn's own site are usually more reliable than the listing's, because the inn has to live with the guest who arrives expecting what it showed.
Three things you will almost never find published, and should ask by email or phone: whether the room you are booking has a bath with a view or a bath with a wall in front of it; whether dietary requirements can be handled in a kaiseki course, which needs notice measured in days rather than hours; and whether the private baths can be reserved before you arrive or only on the day.
Take Mizunosato Marukyu in Shuzenji, on the Izu peninsula, and run the four variables against what it publishes.
The water first, since it is the reason the town exists. Shuzenji's spring is traditionally dated to about twelve hundred years ago and attributed to Kūkai — the story is that he was moved by the sight of a son bathing his father in the cold river and drew hot water instead. The inn, which is around a century old, states that all five of its baths draw on that same source.
Bath. Three bookable private baths, by reservation, charged. The published terms are specific: 16:00 to midnight with the last start at 23:00, on the hour, fifty minutes, 4,400 yen including tax, reserved by phone or on the day up to 21:00. Two of the three — a swimming bath and a lying-down bath — were added in August 2024.
The third was renovated the same year with a sloped entrance and minimal steps for wheelchair and stick users — and, at the time of writing, the inn's own page states that it is out of service for plumbing and equipment repairs.
That pair of facts is exactly why this variable has to be checked on the inn's own site rather than a listing. An accessible private bath is the kind of detail that decides a booking; so is its being closed.
Meals. Served in fully private rooms — the middle of the three arrangements, and the one most guests actually want. One of the six room types pairs an open-air bath with a dining space, which puts that room into the in-room category.
The day. Check-in is 15:00 with a last check-in of 18:00; check-out is 10:00, or 11:00 for some room types. The last-check-in figure is the one to note — it is the constraint that catches people arriving from Tokyo after work, and it is published on the rooms page rather than anywhere obvious.
Scale. Fifteen rooms across six types, including a 240-square-metre premium suite completed in October 2024 that takes the whole top floor. Small enough for personal service, large enough to run three private baths and a separate dining operation.
Run those four against your own priorities and you have an answer without reading a single review. If you want the same exercise for Kyoto, our guide to celebrating an anniversary at a Kyoto ryokan covers a different market, and our guides to what an onsen is and how to bathe in one cover the conventions every ryokan assumes.
Shuzenji is unusually easy from Tokyo for somewhere that feels remote: Kodama Shinkansen to Mishima in about an hour, then the Izuhakone line for roughly thirty minutes. By car it is about forty-five minutes from the Numazu interchange.
The town itself is walkable, and the set piece is the bamboo path along the Katsura River. It runs about 300 metres, from the vermilion Katsura Bridge past Kaede Bridge and on upstream to Takishita Bridge, and the tourist association notes it is lit until eleven at night — so it is better walked after dinner than as a daytime excursion.
Shuzenji also gives the peninsula's other draws within reach — the coast, the wasabi farms of the Amagi valley, and the Izu Kogen art museums — which matters if you are treating the inn as a base rather than the destination. A ryokan of this kind generally assumes you will not leave, and the schedule reflects it — meals at set hours, and a check-out that does not accommodate an excursion first.
One practical note. Not every Shinkansen stops at Mishima — the Nozomi does not — so check the service rather than assuming. From Tokyo the Kodama is the usual answer; from Nagoya the inn's own directions point at a Hikari that terminates at Mishima, which it describes as faster and more convenient than the Kodama.
When to book. The two things that sell out are not rooms but slots: private bath times and the better meal arrangements. Book the room as early as you like, then telephone about the bath. Some inns take the booking by phone in advance and some only on the day; Marukyu accepts either, up to 21:00. Where it is same-day only, arriving early on a busy weekend is worth more than arriving elegantly late.
Where you eat, which bath you get, how long you have, and how many other guests there are. Those four decide a ryokan stay, and every one of them can be established before you book — three from the inn's own pages and one by asking.
The corollary is worth stating too. A modest inn that matches your four is a better stay than a celebrated one that does not, and it will cost less. Disappointment at an expensive ryokan is more often a matter of the configuration booked than of the inn itself — and once the evening has started, the configuration is fixed.
Everything else — the name, the photographs, the star ratings — is downstream of those four, and none of it will rescue a stay where the dinner is in a hall and the private bath was fully booked by the time you checked in.