Thermae Bath Spa
One of the few places in Britain where you can bathe in natural hot-spring water, and in an open-air rooftop location as well, this striking complex designed by Nicholas Grimshaw consists of a Bath-stone building surrounded by a glass curtain wall. The only difficulty is in deciding where to spend more time—in the sleekly luxurious, light-filled Minerva Bath, with its curves and gentle currents, or in the smaller, open-air rooftop pool for the unique sensation of bathing with views of Bath's operatic skyline (twilight is particularly atmospheric here). Two 18th-century thermal baths, the Cross Bath and the Hot Bath, are back in use, too (the latter for treatments only). End your session in the crisp third-floor café and restaurant.
It's essential to book spa treatments ahead of time. Towels, robes, and slippers are available for rent. Note that changing rooms are coed. Weekdays are the quietest time to visit. You must be 16 to bathe here and 18 to book a spa treatment.
