San Franciscans adore the Tonga Room. Situated in the basement of the swanky and storied Fairmont Hotel, the renowned restaurant and tiki bar is, for some of the city’s residents, woven just as deeply into the urban fabric as cable cars and the Coit Tower.

So when Mai Tai fans in the Bay Area first got wind of the possibility of their favorite historic watering hole becoming a casualty of redevelopment at the Fairmont in 2009, they did what any bar preservationists in their right mind would do—they went to happy hour.

“They had a line out of the door every single night of the week for months,” says Otto von Stroheim, a local tiki enthusiast and former publisher of the fan ‘zine Tiki News. “There were like 100 people waiting outside, and this is a restaurant that seats 300.”

It’s not hard to see why the Tonga Room inspires so much loyalty. For fans of all things retro and Polynesian, the décor is nothing short of awe-inspiring—patrons can get down on a dance floor constructed of salvaged wood from a lumber schooner, and ship’s rigging (masts, ropes, and sails) surround the sit-down dining area. A glowing blue lagoon in the center catches “rainfall” from faux thunderstorms that arise every half-hour, also serving as a venue for frequent live performers who play atop a floating barge. In short, there’s nothing else quite like it, in San Francisco or anywhere.

A bit of background: the luxurious Beaux Arts-style Fairmont was built in San Francisco’s Nob Hill neighborhood in 1907. In 1929, an ornate 75-foot indoor swimming pool called the Fairmont Terrace Plunge was installed at the hotel, becoming a magnet for well-heeled locals and celebrities. In 1945, Mel Melvin, Metro Goldwyn Mayer’s leading set director at the time, was hired to turn The Plunge into the Tonga Room, transforming the pool into a central lagoon and constructing the bar and restaurant around it.

“Tiki bars, back in the day, were built in places like the Fairmont,” says van Stroheim. “They were very grandiose and expensive to build. Their clientele were also high-end.”

Aside from a late-1960s update and a 2008 restoration, the bar has remained largely untouched throughout its 69-year history. So why would any hotelier in their right mind want to tear out this gem? Like any trend, the popularity of the tropical tiki bar has waxed and waned. In 2009, the Fairmont’s management questioned the continued viability of the Tonga Room amid plans to remodel and restructure the hotel around new condominiums.

When word of the Tonga Room’s endangered status got out, a grassroots effort to save the bar grew quickly, inspiring petitions, letters to city officials, and a Facebook group that peaked at 4,000 members. The consequent spike in patronage and sales made the Fairmont’s management reconsider their decision for the time being, although the Tonga Room isn’t preserved in perpetuity—the redevelopment plans aren't completely off the table, and they’ve already gained approval from local government entities.

For now, however, the Tonga Room is still serving up tried-and-true classics like the Zombie (rum, fresh lemon, lime, pineapple and passion fruit juices, and bitters) and, of course, the timeless Mai Tai (rum, Curacao, orgeat, and fresh lime juice.)

Frequently cited as one of the most renowned tiki bars in the nation (and jokingly called "the greatest place in the history of the world" by Anthony Bourdain during a 2012 visit) a trip to the Tonga Room is a must for any tiki lover’s bucket list. Here’s the lowdown:

Location: The Fairmont San Francisco, 950 Mason Street, San Francisco, CA 94108

Hours: Sun.-Thurs., 6 p.m.-10 p.m.; Fri. and Sat., 6 p.m.-11 p.m.

You’re having: The Chi-Chi (a vodka-based take on the Pina Colada) and the Steamed Hawaiian Butterfish, served with scallop dumplings.

Best Yelp review: "This place should be some kind of national treasure. It needs to never go away."

The Tonga Room is a member for San Francisco Heritage's Legacy Bar & Restaurant Program. Looking for more great historic bars and restaurants in San Francisco? Check out this guide.