It's an Ubud thing to do, to find a spa/sauna you love and frequent it weekly. For us at Keith's Villa, we went to this hotel spa at least once a week to unwind – what harrowing activities we needed to unwind from, I couldn't tell you. But looking after yourself is a hobby in Ubud and I love this.
Spas are no place for a camera but the walk down to this spa is almost the best part. Upon descending the mossy steps from the road, you're immersed in nature; everything grows on every surface.
The spa itself is beautiful, where you'll alternate between the hot pools, the icy cold pools and the private sauna rooms. This is the Ubud alternative to happy hour, so come at around 5 or 6pm.
Tjampuhan Hotel (ask at the front desk for the spa, visit is US$10), Jalan Raya Campuhan, Ubud, Bali