Images via thermaebathspa.com

The reason I chose Bath University all those years ago had very little to do with the course syllabus. I had been reading a lot of Jane Austen and fancied myself taking a turn about Bath’s Pump Room. But it’s not the Pump Room that brings me back after more than 20 years. My husband and I are here to immerse ourselves in the warm, mineral-rich waters of Thermae Bath Spa, the only natural thermal spa in Britain.Designed by Sir Nicholas Grimshaw, the very modern glass cube housing the main spa building couldn’t be more different from the gracious Georgian architecture that surrounds it. It houses two natural thermal baths, an alfresco rooftop pool and an indoor pool, a steam room and 20 treatment rooms. You can book in for two hours, four hours or a whole day. We book a two-hour spa session (£27 each) and, hoping to beat the crowds, arrive at 9am on a Sunday morning. We head straight for the rooftop pool.We are not prepared for how beautiful this pool is, especially first thing on a bright, autumnal morning. We experiment with the air seats and the bubbling jets, then simply float in the warm water, admiring the view over the city. My husband reflects that Bath might be a great university for our 18-year-old twins next year. I know what he’s thinking: lots more visits to Thermae Bath Spa for their parents.Next up is the series of aromatic steam rooms. Here we sit on the stone slab that encircles the dome-shaped capsule and let the soothing vapours perforate our pores. Then, on a haze of lemon grass, eucalyptus, lotus flower, and lavender, we float down to the Minerva Bath in the basement of the building. All flowing curves and columns, this is the spa’s largest pool and while it doesn’t offer the magic of the rooftop pool, it does boast invigorating massage jets, a whirlpool and a ‘lazy river’ (which we rather enjoy).Our two hours are nearly up and we make a final visit to the rooftop pool. It’s a lot busier than it was an hour an a half ago, so we decide to head for the Spring Café instead. We order a Mandarin and Orange Jigger and a pot of Earl grey Tea. Then, all too soon, it’s time to get out of our wet swimsuits and back to the real world. Thermae Bath Spa has certainly worked its magic on us. All we have to do now is work on the twins…

Further information, 0844 88 0844; Thermae Bath Spa