Hakone · Kanagawa · 箱根小涌園ユネッサン
Hakone Kowakien Yunessun
A swimsuit hot-spring amusement park in Hakone with an indoor lazy river, outdoor hot-spring areas, a warm-water slide and a shallow kids' pool.
Half day during a Hakone overnight.
At a glance
Confirmed, not confirmed, unknown
- Indoor poolConfirmed
- Outdoor poolUnknown
- Water slideConfirmed
- Kids / shallow poolConfirmed
- Open year-roundConfirmed
- Hotel on siteUnknown
- Day-use visitUnknown
- Family rooms (4+ guests)Unknown
Source-backed facts
What the official pages say
Yunessun is at 1297 Ninotaira, Hakone-machi, Ashigarashimo-gun, Kanagawa.
Yunessun is a hot-spring activity zone where guests wear swimsuits; photos and video are allowed.
The River Area has a large indoor lazy river usable year-round in any weather.
The Mountain and Sky areas are outdoor areas.
The park says it can be enjoyed in both summer and winter.
The Rockies Splash slide uses warm water and requires riders to be 105 cm or taller.
Pony Lagoon is a kids' pool 30 cm deep with a 1 m-high slide.
Children not yet out of diapers must wear swim diapers under their swimsuit.
In the swimsuit area, guests with tattoos may enter if the tattoos are covered with a rash guard or similar.
Child pricing applies to ages 3–12; entry is free for children under 3.
From Hakone-Yumoto Station, a Hakone Tozan or Izuhakone bus reaches the Kowakien stop in about 20 minutes.
Editorial planning guidance
How it fits a trip
This is KodoTrip's judgement based on the facts above, not a statement from the operator.
- A good weather-proof half day within a Hakone overnight, because the lazy river is indoors.
Next step
Confirm current conditions.
Planning around Hakone? See the destination guide for pacing.
Related: Indoor water play in Japan for rainy days with kids
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