SIN'S BACK IN FOR VISITORS TO LAS VEGAS.

Byline: - Rob Lowman

LAS VEGAS - The folks in Las Vegas say they never catered to the family trade, but regardless, this locale seems to be polishing up its informal title as Sin City.

While Celine Dion's new spectacular and the upcoming adults-only Cirque du Soleil at New York New York may make the headlines, you'll see billboards around the city advertising pursuits that are a bit earthier. Exhibit A: the Sapphire Gentlemen's Club.

The $25 million, 71,000-square-foot complex calls itself the ``largest and most spectacular adult entertainment complex in the world.'' Devoted to topless dancing, it claims to have ``6,000 of the most beautiful and exotic entertainers.''

Women shouldn't feel neglected, however. USA Today recently spotlighted the trend of bachelorette parties in Vegas, where women can ``misbehave.'' Some of the package deals being offered include stays at major resorts, champagne and VIP access to hot spots where hunky men dance while wearing very little.

Certainly this is in keeping with four national-television commercials that espouse an overt message: Just about anything goes in Vegas. Erika Brandvik of the Las Vegas News Bureau, the group behind the ads, says the campaign was inspired by real stories posted at vegasfreedom.com(U0). She added that there are more ads on the way.

A quick perusal of some of the stories at the Web site doesn't turn up anything too salacious, but the postings suggest that some visitors are leaving their inhibitions at home.

All of this is in keeping with Vegas casting itself as a party destination. (The sight of people walking up and down the Strip with those giant drinks strapped to their backs might give you that impression, too.)

Ultra lounges like Paris' Risque, MGM Grand's Tabu and Treasure Island's Mist are also aimed at a younger, hipper crowd.

But the Flamingo is targeting Jimmy Buffett's Margaritaville to visitors of all ages who like to party, according to Robert Stewart of Park Place Entertainment, which owns the Flamingo, Paris, Bally's and Caesars Palace.

At the latter property, topless bathing is allowed in the Venus pool.

Since the properties are located near each other, this creates a kind of cross-fertilization, which includes other forms of entertainment around the city.

``I think one of the things that attracts people to Vegas is the critical mass,'' Stewart said. ``(People come here to) have the opportunity to do so many things. It opens up the possibilities. ... In a sense, we help our competitors because we have unique attractions, and they help us because they have unique attractions.''

Unique and for adults. ``Family Vegas is gone,'' said Heather Kovacs, who designed Risque at Paris. ``Sex is back with a vengeance.''