Calistoga Hot Springs and Mud Baths

Calistoga is where Napa Valley ends and the spa towns begin, and a volcanic-ash mud bath here is one of the most distinctive things you can do in wine country. The little town at the north end of the valley sits on top of the same underground geothermal system that powers the Old Faithful Geyser of California just north of downtown, and for well over a century its springs have fed mineral pools and mud baths. The ritual is gloriously simple: you lower yourself into a tub of warm, thick mud made from volcanic ash and hot mineral water, lie there for a few minutes while the heat works into your muscles, rinse off, soak in a mineral bath, sweat in a steam room and then rest in a blanket wrap, often followed by a massage. A handful of established spas, most within walking distance of Lincoln Avenue, offer it in different styles. Calistoga Spa Hot Springs has four outdoor geothermal pools at different temperatures and day-use access; Indian Springs has one huge geothermal pool fed directly by its springs; the Baths at Roman Spa are quieter and lower key; Golden Haven offers private mud rooms for two; Dr. Wilkinson's Backyard Resort is known for The Works, a package of mud bath, mineral whirlpool, steam room, blanket wrap and massage; and Solage offers its Mudslide treatment in a resort setting. Moonacre Spa and Baths is often named as a budget-friendly option. Prices vary with the package, and treatments book up on weekends. It is messy, a little silly and wonderfully relaxing, and it is the perfect counterweight to a day of tasting.

A town built on hot water. Calistoga's spa tradition dates to the nineteenth century, when the entrepreneur Sam Brannan developed a resort around the springs and, according to local legend, coined the town's name by mixing up California and the New York spa town of Saratoga. The hot water still shapes the town: motels advertise mineral pools, the main street is lined with spa signs, and the wooden water towers and geothermal steam give the place a small-town, slightly old-fashioned charm that is very different from polished Yountville or St. Helena.

Choosing your spa. For families and groups who mainly want to swim, Calistoga Spa Hot Springs, with pools ranging from about 80 to 104 degrees Fahrenheit, is the easy choice. For a classic mud-bath ritual with old-school atmosphere, Dr. Wilkinson's and Indian Springs are the long-standing names; for couples, Golden Haven's private mud rooms are the draw; and for a luxury afternoon, Solage's resort spa is the splurge. Each spa sets its own rules on day-use passes, age limits and pool access for non-guests, so confirm when booking, and reserve ahead for weekends and holidays.

Practical advice. Do not combine a hot mud bath with a heavy tasting session — heat and alcohol together are a bad mix, so drink plenty of water and schedule the spa after lunch rather than after your third winery. Remove jewelry and bring a swimsuit for the pools; the mud washes off, but some people prefer an old suit. People who are pregnant or have heart conditions should check with a doctor first. Afterwards, stroll Lincoln Avenue for dinner, or drive ten minutes south to Castello di Amorosa if you booked a late tasting.