Columbia Archives manager Barbara Kellner works at a large Danish modern desk that belonged to Columbia's creator, the late James W. Rouse. His eyeglasses rest in the top drawer. His early vision for Columbia surrounds her in the office near Lake Kittamaqundi.

Here, Kellner is free to ponder the sketches and architectural drawings, many of them more than 40 years old. They describe dreamers' visions of Columbia's Town Center -- a place of fresh air and fountains, market stalls and sunlit walkways. Some notes from the time suggest a place evocative of Tivoli, the famed pleasure gardens at the heart of Copenhagen.

But nowhere in the archives can Kellner find anything to explain what became of that place, that vibrant, even magical, town center.

"That's my question," Kellner said.

"Whatever happened to Tivoli?"

She never stopped wondering. And she is not alone.

Beginning Saturday, as they embark on a five-day series of workshops known as a charrette, residents will be asked to reimagine a town center for Columbia. As they look to the future, they may get a chance to rekindle the dream of Tivioli.

In the years since Columbia took shape, office buildings and schools and thousands of houses and apartments have emerged amid lakes and parks. At the center is a shopping mall, ringed by an asphalt parking lot. The lot and busy Little Patuxent Parkway separate the mall from the lakefront that once was envisioned as the true center of the planned community begun in the 1960s. Now, walking from one place to the other involves crossing the busy four-lane parkway or a trekking across a bridge that, with its steps, is inaccessible to those in wheelchairs or pushing strollers.

So whatever happened to Tivoli?

William Finley remembers. He was there when the dream was dreamed and when it got lost in the shuffle.

During the frenetic 10 years he spent helping to plan and build Columbia, starting in 1963, Finley rose to become senior vice president of the Rouse Co.

"Tivoli became one of the things we put into the stew," recalled Finley, now a developer in Florida. "But we were under the gun."

Under the gun, he said, to live up to other commitments the developer made in getting approval to build a city from scratch -- building and selling thousands of houses, luring businesses and building offices -- all on deadlines.

"We had to hit our targets," Finley said in a telephone conversation. "The financial model required it."

To that end, Wilde Lake and Lake Kittamaqundi were dug and filled; residential and office construction proceeded swiftly. The mall opened in 1971 to much fanfare.

"To a person who only has a hammer, every problem looks like a nail," Finley said. "This was a shopping center company. What do you do when you want to make something happen? You build a shopping center."

Finley left Columbia in 1972, moving on to another Rouse project. The economy was sagging. Columbia never got its Tivoli.

"It was an idea that everybody loved," Finley said. "But nobody loved it enough."

Finley regrets that, as he regrets other unfulfilled promises: a public transit system and the pledge to build 10 percent of Columbia as affordable housing.

"The money guys took over," he said.

There may be, however, one more chance to capture the magical town center.

There are 51.7 acres left, near Symphony Woods, where a promise might still take shape. Business leaders, community activists and others will come together during the charrette in a way that perhaps hearkens to the way Rouse once brought together architects and planners with educators, sociologists, religious leaders and others.

General Growth Properties Inc., which acquired Rouse last year, will be there, too, with its vision for the future of Town Center.

Local leaders see it as an exciting moment.

"The charrette is like the time Rouse brought the planners together," Kellner said. "This is not a time for feasibility. This is a time for big dreams."

Ken Ulman agrees.

As a County Council member and Zoning Board chairman, Ulman (D-West Columbia) challenged efforts by General Growth to sell and downsize Merriweather Post Pavilion and build high-density housing on the adjacent 51.7 acres, the last significant undeveloped parcel in Town Center. The giant Chicago-based developer changed its course. Last spring, the company announced plans to keep the amphitheater and make it the focal point of a pedestrian-friendly town center that would include a mix of housing, retail, office and commercial space.

General Growth Vice President Dennis W. Miller said he welcomes the charrette, adding that he sees it as a chance to take a comprehensive look at Town Center.

Ulman thinks the spirit at the workshops will be cooperative.

"Clearly, everyone who looks at Town Center can't help but think it could be so much better," said Ulman, 31, who grew up in Columbia.

"There was supposed to be a Tivoli . . . a really special place. I don't think we have that now."

Some of the elements are here, nearby, Ulman said. The public library, Symphony Woods, Merriweather. But for now, they remain fragmented.

"We have some of the pieces," he said. "Connecting them, for whatever reason, never happened." But, he said, "I don't think we are that far now from creating a special place. A sense of place."

Robert Tennenbaum, who helped plan Columbia and lives there, thinks the need for a more unified town center is real but said the cost must be shared -- by General Growth, the Columbia Association and the county. "People tend to forget it's no one group's responsibility."

Financial feasibility will be a part of the charrette process, Ulman said. He hopes a consensus can be reached about the best plan. People can suggest anything they want. Houses, kiosks, office buildings, walkways. A Ponte Vecchio over Little Patuxent Parkway.

Or glittering lights and tulips, pagodas and a scenic railway: Will Columbia finally get its Tivoli?

Ulman laughs. He's not sure.

"Whether it's Tivoli or something else, people want that special place."

Columbia's planners envisioned a town center evocative of Copenhagen's Tivoli Gardens, above. Below, in Columbia's early days, Bill Finley, left, James W. Rouse and Mort Hoppenfield discuss plans for the town."I don't think we are that far now from creating a special place," said council member Ken Ulman.