Relaxing — deep, immediate muscle release.
Rich in active gases or metals — a strong mineral character.
Soft water — natural, classic buoyancy.
On the slopes of Rincón de la Vieja volcano, in Costa Rica's Guanacaste province, acidic sulfurous water (pH 4) emerges at 60°C, alongside natural mud pools and geysers. Eco-lodges nearby allow visitors to observe the surrounding wildlife.