It’s easy to imagine the burgeoning business of “wellness” as a product of our time, sold on narcissism and exhaustion from punishing work schedules.

In fact, the wellness craze has deep roots. Beginning in the middle of the 19th century, the leisure class grew infatuated with a particular type of healthy getaway: the water cure. By the 1850s, a constellation of spa villages had emerged across 20 states. By 1930, the country had over 2,000 hot- and cold-spring resorts.

Neither the practice nor the result of the treatment—which evolved out of a newfound enthusiasm for bathing—was strictly defined. Hydropathy encompassed everything from a spell in the tub to highly regimented procedures supervised by water doctors with stopwatches. According to its boosters, who were some of the most distinguished medical men of the day, water could cure everything from hiccups to cancer (and even hydrophobia).

Renowned water-lovers included John Roebling, the engineer of the Brooklyn Bridge, who liked to wrap himself in a damp, cold sheet, and most famously, President Franklin Roosevelt, whose interest in water long predated his visits to Warm Springs, Georgia.

Most of these “procedures” could have been performed at public baths, or at suburban facilities such as the Harrogate spa, four miles outside of Philadelphia. But part of the lure was always to get out of the city. For one thing, hydropathy was cast as a cure for the peculiar ailments of the well-off urbanite—a remedy for bourgeois decadence, to heal, as Carl Smith writes in City Water, City Life, the ill effects of the “overly refined life characteristic of cities.” (The equivalent of a modern farm vacation, maybe.)

For another thing, as Thomas Chambers suggests in Drinking the Waters, “taking the waters” was simply an excuse to have fun. And so a vast network of scenic spa towns emerged along the railroads. Built around grand bathhouses, they offered a much more social experience than bathing at home.