The water bubbled around us, a cauldron of Jacuzzi jets and pumps.
Surrounding the bath we sat in were nearly a dozen doors, each leading to its own speciality sauna: aroma of lavender; infra-red; and one where a staff whipped hot air on to guests with a towel while instructing them to emit primal screams.
This is Rogner Bad Blumau, Austria's amusement park of spas. A short drive from Graz and an afternoon's train journey from Vienna, it is the perfect retreat for the businessman looking to blow off a bit of steam.
The spa, which has an attached hotel, is approached through a winding walkway flanked by various species of trees, each labelled with its own Austrian astrology. People born during certain weeks in March, for example, are linked to the weeping willow and are sensitive and intelligent. Getting to know your tree horoscope helps put you in the spa mindset of letting go of everyday worries and focusing on just one thing - yourself.
Arriving at the front desk, you are presented with a pile of towels and bathrobes that will be your uniform for the next several hours. The robes are basic and white, the antithesis to the spa's bizarre architecture of rounded corners and mosaics crafted in primary red and blue. Think of Gaudi, minus the taste.
The aesthetic assault is more than made up for by the water. There is a wave pool that rivals the English Channel for its ferocity, little creeks that allow you to move from indoors to outdoors without ever leaving the water and a sauna of 70°C.
The food is not light and healthy spa cuisine but Austrian basics.
But the thing to savour here are the thermal waters for which Styria is famous. Once the sun sets - facilities stay open until nearly midnight - wander outside to the pool (marked by a large fake volcano) and float on your back.
At the touch of the cool night air, the hot water turns to a mist that floats upward to meet the stars, like an illusory Milky Way.