Hakone Onsen / Grouped by official usage disclosure

For those who want to soak in Hakone's water, straight from the source.Tell them apart by official data — spring analysis & usage disclosure

Booking sites rarely tell you whether the water in the bath flows straight from the source, or has been recirculated, diluted, or heated. The clues are each facility's official usage disclosure and spring analysis. Using this data gathered from our users, we've grouped the ryokan by how the water is actually used — not to rank them, but so you can choose the water you're looking for yourself.

Reading the waterA spring that runs cool is often warmed or lightly diluted in winter to make the bath comfortable.More

Springs that run cool are often warmed or lightly diluted in winter to bring the bath to a comfortable temperature — done so you can enjoy that water. Recirculation and disinfection, on the other hand, affect the water's freshness. Where you draw the line is up to you; so we don't rank, we simply lay out the facts from the official records.

Here, "real" simply means the official usage disclosure shows the water flows from the source — a fact you can read off the records, not a marketing claim.

Listings are organized from official documents submitted by users — composition from the official onsen analysis, water handling from the official usage disclosure. Posting dates aren't collected yet, so no dates are shown.

Information may change. Please confirm the latest details with the facility.