The official unveiling Wednesday of the Mercury statue at Fountain Square in the new Reston Town Center promises to be a happy, consequential event for the 26-year-old planned community in Northern Virginia, symbolizing the partial attainment of a long-cherished, long-delayed goal.

And because of the intrinsically urban ways in which its buildings and streets are arranged, shaped and articulated, the town center has significance regionwide. It represents an important alternative model for the "urban villages" or "edge cities" that have come to dominate the suburban landscape in the past decade or so.

From the outset in 1963, Reston, the unusually comprehensive development in then-bucolic Fairfax County, was intended to combine two worlds -- something of the spaciousness, greenery and informality of the residential suburb with something of the density and hard-edged diversity of the city. But for many years the first part of the equation took precedence over the latter.

Residential construction proceeded along more or less conventional lines, and when public and commercial facilities were added, they tended to be plotted in the suburban mold, with widely separated buildings or building clusters approachable mainly by car. Likewise, when the office boom of the '80s hit Reston, it developed along both sides of the Dulles Access Road in a standard linear pattern of low buildings, each with its ample surface parking lot.

By contrast, the town center, developed by the Reston Land Corp. with Himmel & Co., is a belated bow in the direction of the original notions of Reston founder Robert E. Simon. It greatly benefits, too, from the revisionist aesthetics and urban design ideas of more recent times.

The point needs making that too much should not be claimed for this new place. Created all of a piece, it suffers from this artificial quality, and like other suburban commercial "centers" it remains heavily dependent upon the automobile. It relates as much to the major regional roads as to its immediate setting. Still, the conception here is quite different from the standard development. Though not really a city, nor a town, nor even a center in the traditional sense, this is an extremely interesting hybrid, not entirely unmall-like but emphasizing integration rather than separation of uses, pedestrian as much as vehicular circulation, the unpredictable outdoors over climate control.

Its exceptional quality, from which other virtues flow, is that taken all together it makes an identifiable place. That is, this town center was not conceived in the modernist tradition of homogeneous, enclosed and infinitely extendable space. Rather, it was conceived as a hierarchical system, starting with the pattern of streets and continuing through each part of each building.

Atypical in postwar suburbia, this nonetheless is a familiar pattern, based upon the orthogonal grid of older American towns and cities. There is first of all a "Main Street," here called Market Street, leading to and through a central space, here called Fountain Square. This is the focal point of the recently completed Phase 1, and will remain the principal defining image of the town center as it grows.

More Roman plaza than village green, the "square" is framed on the north by two 11-story office buildings that, reminiscent of Washington's Federal Triangle, form an interrupted hemicycle. They define a generous, comprehensible exterior public space, punctuated at its center by the needed vertical axis -- "traditionally considered the sacred dimension of space," as pointed out in another context by theorist Christian Norberg-Schulz.

Sketched in original plans simply as a copycat obelisk, this vertical element evolved into the baroque Mercury fountain, designed by sculptor Saint Clair Cemin in collaboration with RTKL Associates, architects for the entire project. Cemin's concept of a slightly off-balance bronze figure of Mercury atop a twisting column of Carrara marble, itself dotted with snaillike bronze appurtenances that spew water into a broad-brimmed bowl, is at once traditional and idiosyncratic. Though not exactly sacred (nor precisely profane), it's an appealingly odd blend that gives immediate and promises long-term identity to the place.

From large form to small detail, RTKL's architecture strives to reinforce the strong skeleton of the street pattern and to neutralize the unavoidable condition of being, as it were, an "instant city." The traditional formula of buildings with definable bases, middles and tops is deployed to good effect -- it allows variety within a fundamentally uniform architectural vocabulary. Similarly, a basic palette of colors and materials is established -- limestonelike precast concrete panels, tan bricks, polished pink granite accents, metal balustrades and window frames -- and then subjected to telling variations. The results are a bit formulaic, but the formula is sound.

Phase 1's third mid-rise building, a Hyatt hotel that opened last Wednesday, is a case in point. Located asymmetrically, as if it just happened that way, it also changes the architectural norm distinctively with twin hip-roofed towers, sharp vertical window bays and muscular gray metal detailing. The exposed steel of its semi-cylindrical entrance canopy and the corner towers of the adjacent parking structure are particularly adept. The whole strikes a pleasant modern/moderne note. One only wishes this idea had been pursued in the public rooms inside (designed by a firm specializing in hotel interiors) -- they're beautifully laid out but conservatively and rather tackily finished.

The same theme of variety within limits is played out consistently. The movie house, for instance, which will open in mid-November, makes a strong statement on Market Street with its alluring back-to-the-future marquee. Among architectural details, the metalwork all around deserves a special merit award -- varied in color and form, it has been designed, crafted and placed to differentiate function and heighten visual interest.

Low buildings along this street are shaped with bays, corner towers and arcades, creating a somewhat staccato rhythm. But though variety in storefront design was encouraged, the degree to which this street will distance itself from theme-park, shopping mall norms remains questionable. By and large, the stores, opening intermittently over the next few months, make up the familiar upscale franchise crew.

However, the street itself is splendidly designed -- it's a genuine macadam road for cars and short-term parking, framed by single rows of trees and brick sidewalks. Overall, the town center's sequence of spaces (designed by Sasaki Associates in collaboration with RTKL) is superb. In addition to Market Street and Fountain Square there are two commodious entrance parks with stands of tall oaks, and even though Phase 1 encompasses but five blocks (one occupied by a perimeter parking structure) there are multiple pedestrian pathways from which to choose. One can, for instance, cut through each of the major buildings -- it is the kind of detail that brings a plan, and a place, alive.

Still to come are residences -- at least 1,000 and perhaps as many as 1,600 apartment and row house units -- another hotel, additional office buildings, more parking garages, more stores along an extended Market Street, and an art-science exhibition center. It is encouraging to know that as presently planned these additions will continue along the established, citylike pattern. The citylikeness of the place is the crucial ingredient. No one would mistake this for a real downtown, but its remedial principles of planning and design are worth study and emulation in suburbia.