SARATOGA SPRINGS, N.Y. - On a Friday night 50 years ago this week, folk singer Jackie Washington stepped up to the tiny stage of Bill and Lena Spencer's new coffeehouse.

He was Caffe Lena's first performer, and thousands of singers and countless songs later, the coffeehouse started by the artsy couple from Boston is a folk music icon. On May 22, a half century plus a couple days since it opened, the 85-seat venue -- considered the oldest continuously operating coffeehouse in the United States -- will celebrate its 50th anniversary with a concert by Arlo Guthrie, who has described Caffe Lena as "a national treasure."

Guthrie, whose hits include "Alice's Restaurant" and "City of New Orleans," played at Lena's early in his career and at a few fundraisers held for the coffeehouse over the years. He's headlining the anniversary concert being staged at a 550-seat theater at Skidmore College, located in this horse racing and resort town 30 miles north of Albany.

Mark Moss, editor of Sing Out!, the 60-year-old folk music magazine, called Caffe Lena "almost indescribably significant" to the folk music scene, then and now.

"The core of this music really is about community," he said. "Caffe Lena has created and sustained a community around it."

The venerable coffeehouse is located on the second floor of an old building set amid a bustling downtown entertainment district lined with bistros, bars and boutiques. The entrance, tucked between a restaurant and a comic book store, leads to a narrow, well-worn wooden staircase. At the top, the L-shaped room is jammed with small tables, with a kitchen in the back where coffee, tea and desserts are prepared.

While the many nearby taverns attest to Saratoga's lively nightlife, Lena's no-alcohol policy has been in effect since the day it opened. That, plus the intimate setting, has made it a favorite stop for generations of folk music performers and fans.

"It's like a house party gig. There's something very close and homey and there's no extraneous noise, none of that bar hustle-bustle," said Buffalo native Ani DiFranco, who was just starting out when she performed at Lena's in the early 1990s. "People sit five feet from you and they listen intently."

Bill and Lena split up a couple years after the coffeehouse opened, leaving Lena as the sole proprietor. Over the next three decades, she helped launch the careers of such performers as Guthrie, DiFranco, Bob Dylan, Don McLean, Loudon Wainwright III, Tom Rush, Emmylou Harris and Nancy Griffith, to name a few.

Sarah Craig, executive director of the nonprofit institution that began running the coffeehouse after Lena Spencer's death in 1989, says the venue has managed to retain its '60s vibe while offering established acts and showcasing up-and-coming artists.

"Within the music world this place is sacred ground," said Craig, in her 15th year as Caffe Lena's only paid full-time employee.

"Sometimes people walk in the door looking for a glimpse of a typical '60s coffeehouse," she said. "They looking for the place where Dylan played. It's nostalgic, it's great music, it's a place for the community to gather that's isn't commercial and it isn't church."

The Spencers settled on Saratoga for a coffeehouse mostly because it was a college town, with Skidmore then located just up the street from Caffe Lena. The school would supply a steady stream of customers after Caffe Lena opened on May 20, 1960, giving young people in the area a place to sample the nation's burgeoning folk music scene.

Other folk music venues in Greenwich Village, Boston and elsewhere opened before Caffe Lena, but they've either closed or changed names and locations. Only Lena's has operated continuously at the same address under the same name for the past 50 years, Craig said.

It was a call from Greenwich Village folk musician Dave Van Ronk's wife to Lena that got a young Bob Dylan his first of two performances at the Saratoga coffeehouse in June 1961. That first gig didn't go so well. As the story goes, when Dylan performed, few in the audience were paying attention. At one point, Bill Spencer took the stage to chastise the audience. It didn't work. Everyone returned to their conversations as Dylan resumed singing.

"He was quite upset," Van Ronk, who died in 2002, recalled in a 1989 interview with The Associated Press.

After her husband left in the early '60s, Lena took on every aspect of running a music venue. She booked the acts, introduced them to the audience, handled publicity, paid the bills, even made the Italian pastries and other desserts served by the all-volunteer staff.

"The Caffe is my whole existence, the be-all and end-all of my life," she told the AP in an interview a few months before her death. "My life began almost in 1960."

There were plenty of lean times when interest in folk music waned, but she hung on, never once closing the cafe's doors despite the strain it placed on her personal finances. Things got so bad in the late 1980s that she moved into a back room at the coffeehouse after Saratoga's rents rose beyond her means.

Lena died at 66 in October 1989, several weeks after falling down the stairs at her coffeehouse.

Although so many now-well-known performers had graced her stage, she was emphatic about never claiming to have "discovered" a particular musician. Instead, she took pride in providing a welcoming place for young musicians to hone their craft before a live audience.

"I don't credit myself with discovering any talent," Lena told the AP in 1989. "I credit myself with providing a place to perform early in a career."

Moss said there's still a need for a place like Lena's, especially in the era of music downloads, iPods and social networking.

"In an age where everybody's busy poking each other on Facebook, the idea that you can sit in a small room where amplification is almost not needed and you can almost converse with the artist and sing along, that's a rare thing in the arts," Moss said.