Two thousand years ago, caldariums were the height of fashion. These hot, humid rooms were loved by the Romans, who found that the steamy environment helped them to relax as well as offering some beneficial side effects. Just a few minutes in a caldarium each day and they would find that they had clearer skin, improved respiration, better circulation and lower blood pressure.
And then the sauna arrived, and that was the end of that.
The main difference between a caldarium and a sauna is that a sauna is powered by a coal pit or modern heating technology, while the humidity in a caldarium comes from a hot plunge pool in the centre of the room. In Roman times, this pool would have been heated by underfloor fires manned by slaves – not the most sustainable business model.
Until recently, you would have been hard pressed to find a caldarium outside of Ancient Rome, but they are starting to make a comeback now, as more and more spas turn towards hydrotherapy and traditional wellness models.
Today, the water can be heated in a multitude of different ways, but the end result is the same – a hot, humid space where you can relax and rejuvenate after exercise or as part of your spa experience.