The World Trade Center’s architect, Minoru Yamasaki, considered about 100 scale models before settling on the design that is now etched in our national consciousness. Between 1969 and 1971, after construction had begun on the World Trade Center and before the first tenants went to work there, Alex Tunstall, the director of Minoru Yamasaki & Associates’ in-house model shop, built a final model for presentation to the Port Authority of New York and New Jersey. Tunstall and Yamasaki intended the presentation model, an exact rendering of the site, to reflect the significance and grandeur of the structures it anticipated. Its surface was coated with glistening automotive paint to produce an enlivening sheen. To emphasize the buildings’ unprecedented scale, Tunstall’s team glued 175 miniature cars to asphalt-colored paper streets and placed approximately 300 tiny people throughout the plaza. Most remarkably, the towers themselves rose 7 feet above the 8-by-10-foot base.

Today Tunstall’s model is the only extant three-dimensional record of what were once internationally recognizable symbols of American economic might and are now, in their absence, America’s most emotionally and politically evocative memory. In the wake of September 11, the model was recognized as an indispensable historical artifact, but by that time it had sustained extensive damage from routine handling and years of storage. In 1993 it was donated to the American Architectural Foundation’s Octagon Museum, in Washington, D.C., but funding could not be secured for repairs until after September 11, 2001.

Dimensional Productions, a model-making company in Baltimore, was hired to take on the restoration project. They faced a prodigious task. Pieces had broken off; materials had warped, twisted, deteriorated, and molded; the paper asphalt had turned a shade of tan not found on any New York City street; and 129 small cars and figures had disappeared. After a year of research into the model’s materials by the Octagon Museum, it took Dimensional Productions roughly six months of meticulous handwork to create reproductions of the bits that were lost and to mend, refurbish, and stabilize the existing material. Hundreds of sample replacements were tested before the final replicas were developed. As a result of this scrupulous attention to detail, the fully conserved structure, completed in the fall of 2003, is a virtually flawless technical triumph.

Currently on exhibit at the Skyscraper Museum in New York City, the model reveals the space in a way that photographs and blueprints cannot. It’s truly disorienting to face this eerily perfect reminder of what once was. The towers’ simple intactness shocked me into feeling that the post-September 11 world had been my own bleak, protracted illusion. But the sensation dissolved as soon as it registered, and a nagging unease lingered in its place. This, of course, is a great testament to the power and relevance of the model. It is both a tribute to the majesty of the twin towers and a sobering reminder of the pain wrought by their destruction.