Tabacon Thermal Resort & Spa

In the late 1980s, long before today’s wellness trend hit its stride, Costa Rican architect Jaime Mikowski recognised the healing powers of the Tabacón Thermal River and the Arenal Volcano and set about developing this 900-acre rainforest resort.

Channelling the country’s largest network of natural thermal springs, he constructed waterfalls and pools, planted lush gardens featuring more than 200 native plants and built sleek, fuss-free rooms with walls of glass to bring the outdoors indoors and offer a confidently pared-back refuge from the 21st century.

This is a spa for water babies: the action centres around the mineral-rich pools, which range from 25°C to 50°C, all heated by the now-dormant volcano. One has a swim-up bar and thermal waterslide, others are dotted through the gardens. To intensify that connection with nature, treatments are taken in open-sided thatched cabins and use lotions made from local plants, blending Costa Rican customs with ancient practices from around the world.