The campus of Princeton University is home to some remarkable buildings designed by architects as varied as Ralph Adams Cram, Robert Venturi, and McKim, Mead & White. In the historic center of the campus sits Whig Hall, a small Beaux Arts classical temple with a modernist twist that belongs on this distinguished list of important architecture. The original building was designed for a campus debating society in 1893 by A. Page Brown, a prominent figure in the City Beautiful movement. His design is a perfectly scaled and detailed marble monument of late 19th century classicism.

But it is the modernist twist that makes Whig Hall quite extraordinary for a historic American building. In 1969, a fire gutted the structure, leaving it unusable. Gwathmey Siegel & Associates was hired to renovate the building, inserting an entirely new four-story building within the old walls. But in what may be a first for a historic public building in America, Gwathmey tore off the eastern side of the building and replaced it with a spectacular modernist facade.

The new facade is set back from the original stone wall, and its daring is equal to Michael Graves’ still startling Benacerraf addition (built the same year) to a nearby Princeton professor’s 19th-century house. Of course, Whig Hall is a public structure. And while architects and clients in Europe have no problem merging the historic and the modern, said Princeton architecture professor M. Christine Boyer, “This is almost never done in this country.”

Now Whig Hall has been renovated again—this time by the Princeton firm Farewell Mills Gatsch Architects. Michael Mills from the firm embraced the challenge of the renovation, as it gave them “a chance to consider both the history of classical university architecture and the legacy of late-modern architecture.” The firm enlarged and opened up the small building’s public and gallery spaces to better accommodate students’ contemporary needs. They also made it fully ADA accessible and added wood millwork to distinguish the new additions from the original classical architecture.

While Gwathmey’s renovation is typical of his era’s less precious concern with historic preservation, Farewell Mills Gatsch also offers a sensitive and brave contemporary approach. One can imagine many architects today wanting to delete the Gwathmey addition, but his intervention is what makes the structure so special. The Princeton firm recognized this about the building, and highlighted both the addition and the original A. Page Brown structure. The result stands up well as an object lesson for today’s preservationists who think modern architecture cannot exist alongside older historic structures.