Whether it's a trend born out of nostalgia for decades past or just a fun way to get out and socialize, square dancing has do-si-doed its way into Beijing.

Formal, organized square dancing clubs have been cropping up in Beijing since about 1991, when a Texan expat whose name no one seems to remember introduced square dancing to the Chinese capital. Since then, its popularity has expanded year by year, spread largely by word of mouth.

In 2008, about 25 people, mostly retirees in their sixties, left a much larger square-dancing club to start the Sunshine Square Dance Club, led by Zhang Jian.

For 10 yuan (1.63 U.S. dollars) per three-hour training session, members can practice their moves and pick up some new ones from a seasoned Taiwanese dance instructor and square dance caller.

Authentically clad in imported ruffled skirts and shirts, as well as the occasional cowboy hat, the group mostly dances to lively country music and their moves are as American as apple pie.

The club's practices and events are not all about cutting a rug and making merry, though.

"There is no fixed pattern in square dance. Dancers have to be constantly alert to the callers spontaneous commands," Zhang says, adding, "Those who join us in square dancing have to love a challenge."

Meanwhile, on Friday nights, the Hutong Yellow Weasels can be found playing music, calling square dances and leading singalongs, which they refer to as "hillbilly karaoke," at a small microbrewery located in Beijing's historical hutongs -- the sometimes decaying, often vibrant alleyways of traditional courtyard homes and shops.

In the hipster heart of Beijing, where traditional homes, microbreweries, boutique hotels and shops selling everything from shiny new fixed-gear bikes to vintage clothes intermingle, the Hutong Yellow Weasels play old-timey American folk songs to an audience of foreigners, hip Chinese 20- and 30-somethings and curious passersby.

As in the United States, interest in old-time American folk music is mounting in Beijing. The style came as a precursor to bluegrass and the blues that had its heyday in the U.S., especially in mountainous areas and other places where geography limited interaction with the outside world, in the 1920s and 1930s.

"City people had pianos," Chris Hawke, the Hutong Yellow Weasels' upright bassist and one of its founders, explains. "But you can't get a piano up a mountain."

The band has even had over 100 songs from their "hillbilly karaoke" songbook translated into Chinese, which brings the local audience into the fold, combining something foreign -- American old-timey music -- and something familiar -- karaoke.

"They're bloody, about sex," says Sun Siyu, a Communications University of China student who helped to translate some of the songs. "They're very different from Chinese folk songs."

Sun says she learned a lot by translating the songs, which often contain Biblical and historical references that may no longer even be familiar to many Americans.

Meanwhile, square dancing is, and always has been, a respectable and modest way to let loose and socialize. At a square dance, couples split off into pairs and change partners throughout the evening, if they like, while listening to a caller who tells them what step comes next.

Square dancing is also popular in the streets, where it has taken on some distinctly local incarnations.

On warm summer nights in Beijing, it's hard to walk through any neighborhood or park without hearing bass-heavy electronic music pumping out of a boom box with the volume turned all the way up and someone barking directions into a microphone.

The manic pulsing and thumping of these beats can cut through even the balmiest air like a knife through butter, and one could be forgiven for assuming that the people dancing to it might be hard-partying young people, raging hard into the night.

In fact, it's not Beijing's young and hip--it's their parents and grandparents.

Hawke is quick to point out that the Hutong Yellow Weasels' shows have a lot in common with these groups of square-dancing grannies, though they're able to draw a younger crowd to their hootenannies.

"Kids, you know, they feel dorky going to dance in the park with their parents," he says. "So, we're doing pretty much the same thing, but they feel less dorky about joining in."