Since ancient Rome, people have believed in the physical and mental healing powers of hot springs, which, in the American South and West, are still popular tourist destinations. U.S. spas promoted mud baths in the 1940s, and the '70s brought in-home saunas and hot tubs. Now comes the next step in the quest for holistic relaxation: salt caves.
Eastern Europeans have long thought that just sitting in naturally occurring salt caves could relieve allergies, asthma, eczema, hypertension, ulcers and stress. Recently, they've built simulated caves in the U.S. The Chicago area, because of its large Polish population, is the epicenter of...