I was in japan for the first time earlier this year for 6 weeks. I travelled around with my japanese girlfriend and the first night we spent at a traditional inn in Hakone were we booked a private onsen later at night.
In short: It was amazing. It smelled a little funny at first but it felt incredibly relaxing, my skin felt really good afterwards and it was perfect to recover from the 16 hours of flight earlier. At home I also regularly take hot baths in the bathtub but it can't compare at all with the night sky view and the whole ritual around it.
I'll be back in japan this october for an extended amount of time and I will absolutely go to onsen every chance I get.
In short: It was amazing. It smelled a little funny at first but it felt incredibly relaxing, my skin felt really good afterwards and it was perfect to recover from the 16 hours of flight earlier. At home I also regularly take hot baths in the bathtub but it can't compare at all with the night sky view and the whole ritual around it. I'll be back in japan this october for an extended amount of time and I will absolutely go to onsen every chance I get.