Simon Calder: The man who pays his way in the USA

Follow the latitude of luxury at 35 north

Indulge me, if you will, while I explain my favourite American indulgences. They are a long way from the elaborate and intimate spa experiences that Juliet Kinsman invokes: I prefer foliage to exfoliation, and like my hot springs natural. For the latter, the southern half of the USA is steamiest and best: the line of latitude 35 degrees north provides a succession of misty outdoor locations in which to plunge.

First stop on the latitude of luxury: Jemez Springs, north of Albuquerque in New Mexico. High in the hills, you can reflect that humanity has probably been easing its weary bones over the smooth rocks and into a steamy fissure for millennia. Head east along th 35th parallel to immerse yourself in some style in the town where Bill Clinton grew up: Hot Springs in Arkansas. Bathhouse Row comprises a string of grandiose sanatoria created in the 19th century to harness the healing powers of naturally warm water.

Further east, you reach Greenville, South Carolina – home to hotsprings.com, which turns out to be a manufacturer of indoor spas. But Greenville, the city previously known as Pleasantburg, happens to be the closest South Carolina city to the Appalachian Mountains – where more modest indulgence awaits. The 2,000-mile Appalachian Trail (below), is speckled with 250 lean-to shelters. They may have three walls rather than the more customary four, but are still several steps up from the tent.

Walk far enough north-east and you can wander off the "AT" along the Molly Stark Trail in Vermont. Celebrating a revolutionary war heroine, it threads through some of New England's finest scenery. As early as 1914, The New York Tribune promised that tourists could find "A first-class hotel at the end of each day's run" – these days, with hot water.