NEW YORK (Money Magazine) - From the Pilgrims to the Branch Davidians, America has long been a haven and spawning ground for disaffected clans seeking to start Utopian communities and achieve heaven on earth.

The most fertile time for this phenomenon was the 1800s, when several factors -- lenient immigration laws, Manifest Destiny, the promise and excitement of a new nation -- converged to make America a magnet for groups like the Harmonists, whose village is among many Utopian sites that have been preserved as living museums, complete with guided tours.

While touring a Utopian site is in some ways much like visiting any historical village -- here's the blacksmith shop, here's the general store and so on -- a Utopian tour has the added backdrop of the group's beliefs and lifestyle, which were usually, shall we say, a tad eccentric. Imagine Colonial Williamsburg populated by Trotskyite flat-earth worshipers, and you start to get the idea.

I've always been intrigued by Utopian groups, and not just because Utopia is such an inherently seductive concept. Utopian leaders -- typically charismatic figures with messiah complexes, like George Rapp -- were usually fascinating head cases. And their civic frameworks, which tended to be communal, with members renouncing private property, were often grand social experiments.

Let's begin with George Rapp and his Harmonists, nearly 800 of whom came to America in 1804. Some time around 1790 Rapp, a planter and self-proclaimed prophet, was stirring things up in Germany. He'd publicly rejected the Lutheran church -- a serious offense in Germany at that time -- and was preaching his own form of Christianity, prompting repeated conflicts with church and governmental officials. By 1800, Rapp and his followers, who called themselves Harmonists, had decided to leave Germany and establish a settlement where their religion could flourish. Happily for them, across the ocean was a new country where religious freedom had been codified into law: the United States of America.

After two short-lived settlements, in 1824 they acquired 3,000 acres in what is now Ambridge, Pa., just northwest of Pittsburgh. This site, which they called Economy, was their home for over 80 years. Today a portion of it remains as Old Economy Village, a beautiful, six-acre collection of houses, workshops, gardens and exhibits.

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Rapp preached that Christ's Second Coming was imminent, so in 1807 the Harmonists adopted celibacy in order to purify themselves for the great day. Their notion of purification, however, didn't apply to alcohol, which they made for both their own consumption and outside sale. The massive underground wine cellar, featuring a vaulted ceiling and the original oak fermentation barrels, is among the most impressive sights at Old Economy. Moreover, the entire village is crawling with grapevines, just as in the 1800s -- not only in designated vineyards, but also on stone walls and the sides of buildings. It isn't exactly creepy -- after all, they're just grapes -- but something about it seems oddly askew, which is a good way to think of Utopian sites in general and of the Harmonists in particular.

The Harmonists attracted occasional new followers over the years, but celibacy ultimately winnowed their ranks, and the last two living members dissolved the group in 1905. Celibacy has also taken a toll on the Shakers, probably America's best-known communal utopists. Founded in the late 1700s by the British visionary Mother Ann Lee, who believed she was the female incarnation of the Second Coming, the Shakers at one point had some 5,000 members living in 19 villages from New England to Kentucky (one of which, in Maine, is still active, although now with only a handful of adherents). Many of these sites have been preserved, most notably Hancock Shaker Village in Pittsfield, Mass., which was established in 1783 and active until 1960.

Hancock is still a large, sophisticated site, with a working farm and 20 meeting halls, residences, workshops and other buildings, several of which -- particularly the 1826 circular stone barn -- are architectural gems. Knowledgeable employees explain Shaker life. I especially liked the kitchen demonstration, where a staffer made bread and pies in a wood-burning brick oven and fritters in a huge lard fryer. Mother Ann's dictum to "Set your hands to work and give your hearts to God" is evident everywhere -- not just in words but in the stoic, hard-toiling spirit of staffers, who show how to make the furniture and crafts for which the Shakers are best known. At some points, this virtuous lifestyle seems inspiring; at others -- such as when you learn that the Shakers enforced gender separation so strictly that men and women had separate entrances to their residences -- it seems rather grim. Either way, however, the Shaker story is an engrossing one, and it's easy to spend an entire day here.

Although the Harmonists and Shakers were swimming against the actuarial tide, so to speak, not all Utopian groups were celibate. Quite the contrary, in fact, in the case of the Perfectionists, a 250-member group founded in 1848 by John Humphrey Noyes, a defrocked Vermont preacher. Noyes advocated "complex marriage," in which each man was considered a husband to all the community's women, and each woman a wife to all its men -- in short, free love. Parent-child bonds and even close friendships were discouraged in favor of strict communalism, with children raised collectively by the entire group, and living arrangements periodically rotated to prevent any members from becoming too closely attached.

Bizarre as this all might seem, the Perfectionists (so named because they believed the Second Coming had occurred in A.D. 70, making humans free from sin and thereby capable of achieving perfection) were a successful, functional community. They lived together for 32 years, primarily in a huge Victorian mansion in Oneida, N.Y. This building is now preserved as the Oneida Community Mansion House, where visitors can take guided tours and learn about other aspects of Perfectionist life, which included: tomboyish female clothing and hairstyles that were quite progressive for their time; a eugenics program that resulted in 58 selectively bred children; and a novel form of birth control, whose precise details are best left for your guide to explain (trust me). You can even stay the night in the mansion's comfortably refurbished rooms, though free love, alas, is not among the guest services offered.

Like most Utopian communities, the Perfectionists supported themselves via assorted businesses, one of which was manufacturing silverware. When the community dissolved in 1880 -- in part because Noyes, fearing morals charges, had fled to Canada -- the silverware enterprise was incorporated as Oneida Ltd., which is still locally headquartered and has become a world-class brand. Along with Shaker furniture and Amana appliances, Oneida flatware is among the most visible and surprising examples of how these fringe groups have intersected with mainstream American life -- tangible remnants of heaven on earth.

Zoar Village State Memorial -- Much like George Rapp's Harmonists, the Zoarites were breakaway German Lutherans. Helped by a loan from the Quakers, they acquired land in eastern Ohio in 1817 and lived there communally until 1898. Ten of their buildings, including homes, businesses and trade shops, are exhibited via guided tours, as is a massive garden with a biblically inspired design, planted in 1828.

The Amana Colonies -- Founded by German Inspirationists in 1855, the seven communal Amana colonies gave birth to Amana Refrigeration, now a popular appliance brand. Many homes and businesses can be toured, but Amana may have become too successful for its own good--awash in Ye Olde Curio Shoppes and the like, it's now more redolent of hucksterism than of history.

Koreshan State Historic Site -- Once home to 200 members, this site was founded in 1894 by Cyrus Teed, a New York physician who believed that the earth was hollow and that the rest of the cosmos existed inside of it -- a contention he and his group "proved" with homemade scientific instruments. Twelve buildings remain for public tours.

Historic Rugby -- Not all Utopian sites were religiously inspired. This one, founded in 1880 by the British author Thomas Hughes, was designed to cultivate the civic and social potential of the second sons of prominent English families, who under Britain's gentry system received no title or wealth and were discouraged from learning a trade, leaving them ill-equipped for adult life. The experiment flopped, but several Victorian buildings remain, as does Hughes' impressive library, stocked with some 7,000 titles.