Why should you go there and how do you do it right?

Authentic onsen are scarce in Bangkok, which is why this one, tucked away on a side street in Si Lom, is always packed. The hot springs are the main attraction here. While wellness treatments are also offered, those who come solely for a massage will miss out on what makes the visit so worthwhile. Come to relax and book your treatment afterward.

This isn't a touristy spa with lemongrass and gongs. Japanese bathing etiquette applies, which means showering thoroughly before bathing and generally speaking quietly. If that appeals to you, you'll love it. If you're looking for a social spa afternoon with friends, you should look elsewhere. The cleanliness of the facility and the attentiveness of the staff are repeatedly praised, which is especially important in a communal bathing setting.

My tip: Go late. It's open until midnight, and the last few hours are quieter than on a Saturday afternoon when it gets very crowded.