I believe Sansuk does charge a lower entry for Thais. If you look at the sheet the cashier records your entry on there will either be 250 baht or 170 baht written. Presumably the lower amount for locals or younger guys.
Whilst Babylon may have closed this does not mean the end of saunas. I am not aware of a new sauna that opened in 2020 being mentioned on the forum.
KRUBB - Sukhumvit, BTS Prakanong
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