Developer Milton Peterson has always thought of National Harbor, the proposed $2 billion complex of hotels, offices and shops in Prince George's County, as his version of Barcelona's Las Ramblas on the Potomac.

Not familiar with Las Ramblas? Think Baltimore's Inner Harbor -- only bigger and brighter.

Architects from eight companies had drawn sketches, he said, but none truly captured what he envisioned along the riverbanks in Fort Washington, overlooking Alexandria.

Yesterday, as he and Prince George's officials unveiled an elaborate, 8-by-10-foot, fully lighted model of a $400 million section of the site, Peterson said he hoped that residents and retailers now have a better idea of what he has been talking about since he purchased the property nine years ago.

Dozens of restaurants line the river. Sailboats float off one of the development's two 700-foot piers. A tree-lined main street is filled with one-inch figurines of tourists and residents. A neon sign sits on the river's edge. Twelve-story buildings with shops and condominiums sit a block away from the water.

"Be proud of it," Peterson told the onlookers. "We are."

Donna Edwards, once one of the project's staunchest critics, looks forward to getting reaction from residents. "I don't think people have had a really clear concept of what it means to have that much development on that space," Edwards said. "It's like a little city in itself. It's truly urban."

And that's what worries Alexandria City Council member Andrew H. Macdonald (D). "It's like putting Tysons Corner on the Potomac River," said Macdonald, who fought the project long before taking public office. "This is glitzy and it's inappropriate. . . . While it may generate tax base, it's not the best use of Potomac River waterfront."

The display, which cost almost $400,000 and was constructed by Development Design Group Inc., will be used as Peterson and county officials continue to market the project to residents, retailers and restaurateurs.

"The feeling is if you put that much effort into a model, there's a reasonable expectation that [the project] will move forward," said MJ Dame, communications director for Development Design Group Inc. of Baltimore. "It reassures retailers and leasers."

A dearth of quality shopping options has long been a sore spot for Prince George's, a predominantly black county with a high median income whose residents have felt snubbed by the retail industry.

"This model is a symbol that the dream has become a reality, and National Harbor is another sign that Prince George's is on the map," County Executive Jack B. Johnson (D) said yesterday at the county administration building in Upper Marlboro.

Dozens of county employees applauded and let out a collective "ooh" as Johnson unveiled the display.

It was the model's second public appearance. Johnson used it last month during a major shopping center convention in Las Vegas, and it will remain on display at the county administration building until Friday.

Peterson, the man behind the revitalization of downtown Silver Spring and the development of Fair Lakes -- 7 million square feet of residential, retail and office space in Fairfax County -- has never gone to such lengths on a project.

"This is larger than Old Town Alexandria," Peterson said. "It's like building a city, and we can't foul it up."

The display, which represents about 10 acres of the 300-acre project, does not include Gaylord National Resort and Convention Center, which is expected to be completed by 2008.

Aside from Gaylord, Peterson will not discuss who or what else may be part of the project.

"We haven't announced that yet," he said. "Let's just say that I haven't talked to a hotel that hasn't wanted to come."

Developers hope that a $400,000 model of National Harbor helps sway residents and retailers to support it."We can't foul it up," Milton Peterson said of National Harbor.