As a child in Seoul, I spent countless hours in neighborhood mokyork (bathhouses) watching my mother move from sauna to tea-infused hot tub to cold plunge from my perch on a small wooden stool. Periodically, she'd come over to tell me how wonderful it felt to sweat out her impurities. Later, in my teenage years, my mother finally coaxed me into a jade igloo-shaped sauna—a hanjungmak. I breathed in the hot, dry air until a pool of sweat formed on my burlap mat. Afterward, she dumped a bucket of ice water over my head, and suddenly I understood. The quick transition from nearly painful heat to icy relief was refreshing and oddly soothing.

After I moved to America, I went in search of a mokyork with a hanjungmak and traditional scrubs (the kind in which Korean technicians rub skin and dirt off in long brown strands one gleefully called spaghetti). During the past two years, I have watched (and patiently waited) as the seedy Korean bathhouses in Los Angeles's Koreatown and in the West Thirties of Manhattan have paved the way for three spas with mokyork-inspired treatments.

Following a traditional ground-cucumber facial at Los Angeles's Spa Mystique (2025 Ave. of the Stars; 310/551-3251;; scrubs from $50), guests receive a vigorous sloughing. The therapist's hands, tucked firmly into red-cloth mitts, explore nearly every fold and crevice of the body. Across town, the Aroma Spa & Sports (3680 Wilshire Blvd.; 213/387-2111;; scrubs from $35; access to clay and stone rooms is $10 with a $60 treatment) has a men-only maekbansuk stone room (which purports to turn fat into sweat), and a women-only hwangto mud sauna (Seoul aestheticians claim that a session eliminates toxic heavy metals from the blood).

In New York, Juvenex (25 W. 32nd St., fifth floor; 646/733-1330;; scrubs from $50) is an authentic and stylish reinterpretation of the best Seoul mokyork. Rejuvenating jade—17 tons, to be exact—has been imported from Korea to create the hanjungmak, the tiles on the walls, and the seaweed-, honey-, and ginseng-infused tubs here. The funky décor (curvy sofas, waterfalls, river-rock beds), Western-style juice bar, and open-all-night hours lure nocturnal types looking to be pampered at any time. When it first opened last fall, I brought an American friend. She was glowing after her vigorous scrub, but admitted that having a bra-and-panties-clad masseuse climb on top of her (the norm in Seoul) took an open mind to enjoy. Mokyork devotees like me, however, are delighted to have discovered a bit of Seoul in the heart of New York.
—Janice Lee