Cradled on all sides by the snow-glazed peaks of the Wasatch Range, Salt Lake City, Utah, at the turn of the millennium awaited the invasion of the 2002 Winter Olympic Games: some 3,500 athletes and coaches, 10,000 media personnel, and 70,000 daily visitors. These guests, and the billions watching the telecasts beamed to 160 countries, would quickly learn that this is a city like no other in the United States.

There are arcane liquor laws to navigate. In most hotels an unfamiliar volume of scripture is carefully placed in the bedside drawer of each room. The geography of the town centers on a 10-acre complex known as Temple Square, with every address determined by how far a block radiates from this sacred center. By the dictate of its founding prophet, the town's layout has 132-foot-wide streets, broad enough for turning a train of four oxen and a covered wagon. The centerpiece, a multi-spired block of gleaming granite topped by a gilded trumpet-blowing angel, is a temple of secret rituals with precincts forbidden to tourists and TV cameras.

Diagonally across the street from Temple Square is the large, fashionable ZCMI Center Mall. The initials stand for Zion's Cooperative Mercantile Institution. The majority stock in this company is held by the city's dominant institution, the Church of Jesus Christ of Latter-day Saints (LDS), known to all as the Mormon Church. Inside, beyond the beehive-imprinted sidewalks and near the usual chain boutiques and food court, is the huge Deseret Book outlet. It is stocked with thousands of titles, conference tapes, and pictures of church officers, but there is no Starbucks coffee bar. That would violate an unbreakable church tenet. Along with Mormon titles, surprisingly, the store carries Billy Graham's autobiography Just As I Am and many titles by the 20th century's best-known apologist for orthodox Christianity, C.S. Lewis. A stack of survival kit boxes with emergency essentials, including first aid and water purification supplies for use in time of disaster, stands prominently displayed near the cash registers. Deluxe version: $181.50. Down the hall a small shop features temple souvenirs, white slippers, and simple, long, white, part-polyester dresses for temple wear, bearing labels like "For Eternity," "Forever Yours," and "Angelique."

The majority of the shoppers, like 70 percent of Utah citizens, are Mormons. This is their headquarters city, their Olympus, their Zion. Mystery continues to surround their church. Though it is hard to imagine when contemplating this placid valley with its prosperous metropolis, no religion in American history has aroused so much fear and hatred, nor been the object of so much persecution and so much misinformation. Mormons are intensely patriotic Americans; they even believe the Constitution and the democracy it enshrines were divinely inspired. Yet their own church is rigidly hierarchical, centralized, authoritarian, and almost uniquely secretive. It is also, relative to size, America's richest church, with an estimated $25 to $30 billion in assets and something like $5 or $6 billion in annual income, mostly from members' tithes.

The church began in upstate New York in 1830 with six members. By 1844, when a lynch mob assassinated its 38-year-old prophet, Joseph Smith Jr., the flock had already grown to over 26,000. During the past quarter-century it has moved up to seventh place among America's church bodies, bypassing the Presbyterians, the Episcopalians, and the Lutheran Church-Missouri Synod. Heading into the 21st century, the church's membership had surpassed the 10 million mark internationally, with more than half the members living outside the United States. The faith is expanding so rapidly that the non-Mormon sociologist Rodney Stark projects that during the coming century-with something like 265 million members by 2080-it will become the most important world religion to emerge since the rise of Islam some 14 centuries ago.

Salt Lake's founder hardly had the Olympics in mind when he viewed the Great Basin in 1847 and supposedly declared that "this is the right place" for his bedraggled band of pioneers to dig in and settle. But somehow one suspects Brigham Young might have enjoyed the 16-day party and have been grateful for all the attention focused on the city he built. The church made no direct contributions to the International Olympics Committee, but church-owned businesses, including radio and TV stations and the Deseret News newspaper, gave about $211,000 to the bid committee and helped with media projects. The head of the local committee until 1997 was LDS member Thomas Welch. Churchgoers were prominent among the 15,000 local Olympic volunteers who signed up.

The city had tried for more than two decades to land the Olympics; Utahns were eager to update the city's image as a cow town populated by bland religionists. But the years preceding the Olympics carried reminders that the Salt Lake area, with a population now over 1.2 million and growing fast, home to biotech industries as well as church office buildings, can escape neither the problems endemic to contemporary urban life nor the controversies of its colorful Mormon past. The city has smog, sprawl, and Tongan-Samoan gang wars. Bribery scandals over the Salt Lake bid for the Games sullied the clean-cut image of both the Olympics and Salt Lake City. And polygamy hit the national news again as the activities of some splinter Mormons became a joke on late-night TV. Mainline Mormons were keenly sensitive about all that.