What should a historic district look like? The question is a philosophical sand trap.

For many people, the most appealing solution, and the most naïve, holds that a historic district should today look exactly as it did at some point in the distant past. This reverent treatment does not ensure that buildings will be true to history, however. Preservationists cringe at the mention of historic Williamsburg, Virginia, where the Rockefeller family prettified a colonial village far beyond anything our pre-revolutionary forefathers would have recognized.

Another approach, equally questionable, is to fill in the empty gaps between genuine historic buildings with pseudo-historic stuff, with the end result of making both old and new look equally cheesy. Think of downtown Santa Barbara, with its absurd but rigorously enforced requirements for Mission-style buildings, as well as much of Philadelphia, where Colonial kitsch poses as patrician dignity.

The other extreme, which I think preferable to either of the above, is to maximize the contrast between historic and modern with buildings that are aggressively modern — either the corporate steel-and-glass look or the crazy angles wrought by Frank Gehry’s followers. But purists consider this approach insensitive and out of place, even if some contemporary, curtain-wall buildings actually look pretty good amid the venerable brick piles of Cambridge, Massachusetts.

With all these alternatives rejected, we find our choices limited and none too exciting. We are asked to design buildings that are neither too modern nor too historic. Not only should the buildings be attractive, but they should be modest, too, to give primacy to the historic buildings. Architect Robert Venturi suggested this during the 1960s, with his notion of “background buildings.”

This was the quandary facing the Olson Company, a Seal Beach-based apartment and townhouse developer. In 2001, Olson proposed Harbor Walk, a residential mixed-use project in the downtown historic district of Benicia. This quiet town in Solano County has plenty of history, much of it dating from before the Civil War. The city briefly served as the state capital for a few years during the 1850s, and the old capitol, a handsome, red-brick building with a tall portal framed by Doric columns, is an appealing reminder of frontier democracy. The city’s heyday spanned the years from 1879 to 1930, when the Southern Pacific trains stopped at the water’s edge and passengers boarded boats to cross the strait.

With much of the historic waterfront area intact, Benicia would make a pleasant stopover for tourists traveling north from San Francisco or San Jose to Napa or Sacramento. Instead of a single style, downtown Benicia is a mix of brick buildings from the 1880s, including the old rail depot, wooden commercial buildings, some ornate Victorian homes, and an art deco movie theater from 1918. But like most historic areas, downtown Benicia has plenty of “missing teeth,” and a successful commercial area needs to fill those gaps with new commercial buildings, hotels and housing.

As the first residential mixed-use project in the city, Harbor Walk went through an exhaustive approval process. The developer spent more than a year conferring with local residents and historic preservation groups on the design. The city’s guidelines were strict: The city would allow nothing more than two stories, and nothing taller than 30 feet, even though Olson had initially proposed three- and four-story structures.

To build a project with 8,000 square feet of retail space and 36 for-sale townhouses, Olson decided to divide the project into eight buildings, each just under 30 feet in height. The buildings are arranged on the block in a U-shape, with combination retail-and-residential buildings facing First Street and the other buildings, entirely devoted to residential units, standing immediately behind the street-front buildings, almost out of sight. A broad alleyway at the center of the block contains retail parking and a walkway.

To respect the two-story height limit on First Street, the Olson Company designed buildings with two-story facades. These simple-looking buildings are complex on the inside, though, and can almost be described as two buildings of identical height. The first “building” has two levels — retail space below and residential space above — while the rear volume has three levels, with parking for homeowners at street level and a two-story townhouse above. (Inserting the parking directly beneath the housing is known in the home building trade as a “tuck under.”) The all-residential buildings are all three stories, again with parking “tucked under” two-story townhouses.

Olson project manager Joe Bradford is pleased that the entire block will be filled with development upon completion in 2005. “Downtown Benicia will have critical mass,” he said, adding that the project will set the tone for pedestrian-oriented design. Perhaps that tone has already been set, as other developers are proposing a similar mixed-use project across the street.

Then there is the uneasy question of architecture. In Olson’s first scheme, which was later scrapped, the developer had proposed buildings with wood detail that was somewhat reminiscent of the Old West. In the current version, the facades of the buildings borrow design motifs from surrounding buildings, including elements from a historic tannery and some nearby Victorian houses. If the result is a little too historical for my taste, the buildings are still clearly contemporary, and are not direct imitations of historic antecedents — unlike the example set by Los Angeles developer Rick Caruso, who used the form of a 19th Century railway station for an Abercrombie & Fitch outlet in The Grove, the wildly successful shopping environment in LA’s Fairfax district.

As for the Benicia buildings, we will reserve final judgment until they have been up for a few years, and allowed to weather in the salt air. Maybe they will be fine for a touristy-but-tasteful downtown of small hotels, beds-and-breakfasts and brunch fare. Apparently, we have to sprinkle a little Williamsburg onto historic districts to make them attractive to visitors. This is a price we willingly pay to preserve old structures in a relentless real estate market. If history cannot be recaptured, neither need it be entirely lost.