This place dates back to the 1800s, when Bath was really in its Austen-era heyday. While its sturdy, neo-classical framework hasn't changed, things look a little different inside today. Clad with sharp-as-you-like art-deco mirrors and upholstered in shades of moody aubergine and sopping wet clay - courtesy of New York-based Champalimaud Design, we should add - this hotel is the place to go for classic luxury. The spa itself is a patchwork of 11 treatment rooms which sit around a classical bathhouse teaming with thermal pools.

You might have thought we have five senses, but the experiences at this coastal SoCal hideaway are so especially spine-tingling, that you'll leave convinced there are perhaps several more. Yoga on the beach, Evan Healy facials and energy healing sessions are all on the menu. It even has a prenatal package that lavishes mums-to-be with extra pampering.

There are times, while staying at Bisma Eight, that it feels as if you're floating - not necessarily due to the sheer elation elicited by its vibrant Balinese restaurant, but because of the vast mirror-like pools which create leafy dioramas throughout the hotel. When you aren't busy destressing in its ostentatiously large infinity pool, why not try out some Balinese temple-flower aromatherapy or ease into a somnolent butter massage?

Tulum isn't short on designer hotels, though it can be a little tricky to find somewhere that really embraces local customs. Habitas Tulum offers the best of both worlds. Expect tented rooms and antique furniture and set among swarming Yucatan palms, a lip-smacking restaurant and a wellness program that includes Mayan clay rituals, cacao ceremonies and bespoke, medicinal treatments distilled from the surrounding wilderness.

We love a zhuzhed-up motel. This retro-style pit-stop-turned-luxury-hotel In the trough of the Napa Valley combines all the trinkets and paraphernalia you might expect to find on a great American road trip with mid-century furniture and a surprisingly sprawling spa that dishes out a variety of off-the-wall treatments. Aside from its three geothermal pools, all sourced from Castiloga's natural underground hot springs, and a meditative spa garden, expect CBD-infused deep-tissue massages and DIY mud bars.

Expect Shangri-La and then some. Yes, this oasis in the clouds is home to all the typical spa amenities - steam rooms, pools, etc. - but the real draw is its herb-infused treatment menu which makes full use of the surrounding natural bounty. Book in for a Tibetan Ku Nye massage or, if you're really brave, a spot of Chinese moxibustion whereby dried mugwort is burned near your body's meridian points to help stimulate the flow of Qi energy. The staff here are serious experts in Bhutanese herbal medicine, always willing to take guests on nature hikes through the majestic Neyphu Valley (you'll want to bring a notebook, trust us).