This massive extravagance, a 40-room mansion modeled after the English castle at Alnwick, helped put Trumbauer on the map. Costing roughly $6.6 million in today’s dollars, the home for sugar baron William Welsh Harrison in suburban Glenside, Pennsylvania, was a menagerie of styles and flourishes, from mantlepieces and cabinetry inspired by the chateaus of France to the mirror room, painted with a mural depicting the seasons as women, surrounded by zodiac signs and cupids. One of the nation’s largest homes when it was completed in 1893, the complex was donated to Beaver College (now known as Arcadia University) in 1929. Students recount numerous legends about the buildings, including tales of the secret passageways Mr. Harrison used to conduct numerous illicit affairs behind the back of his wife.

A summer escape for the aristocrats of the Gilded Age, Newport, Rhode Island, has seen plenty of flashy homes. But Chetwode, a limestone-clad chateau Trumbauer designed for the Wells family in 1903, is considered one of the most lavish of the lot. Salons covered in white and gold decoration recalled the ostentation of Versailles, while paintings by old masters lined the walls. Later owned by the Astors, the building was demolished in 1973 after a chimney fire damaged multiple rooms (the stable garage is now the site of condos).

Trumbauer was no stranger to Newport, however, having previously designed this Beaux Arts beauty (now a national landmark and open for public tours) for Edward Julius Berwind. Finished for roughly $1.4 million in 1901, the manse takes its design cues from the 18th century chateau d'Asnieres outside Paris, and the then in vogue French classical style. The home was a showpiece and statement of the owner’s social stature; Berwind, who made his money in the coal trade by supplying the U.S. Navy, among other clients, was as well-known a mogul at the time as Frick, Carnegie or Ford. Though Trumbauer never studied overseas, like many of his peers, he was a stickler for period details and accurate reproductions, and the Elms still stands as an exemplary model of French revival architecture. The three-story home boasted a grand facade, a garden with marble terraces, and numerous period details and furnishings; the grand ballroom, which contains the original crystal chandeliers, is still a highlight.

Now part of Monmouth University and known as Wilson Hall, this magnificent private residence, built in 1929, showed Trumbauer collaborating with Julian Abele, a pioneering African-American professional architect and chief designer at his firm. Designed as a home for Hubert Templeton Parson, former Woolworth Co. President, and his wife Maysie, this neoclassical French structure featured 50 types of Italian marble, limestone from the same quarry that supplied the Empire State building, and a 24 -by-93-foot rug in the grand hall that was specially made in the Canary Islands. It’s always been a location associated with wealth; it was previously the home of another grand aristocratic mansion owner by Hubert Parson, which Woodrow Wilson used as a summer White House in 1915, and the existing building was used in the film version of Annie to portray Daddy Warbucks’s home.

While technically done under the heading of Horace Trumbauer’s eponymous firm, the design for the Philadelphia Museum of Art is considered the work two other architects in his employ: Julian Abele and Howell Lewis Shay. Finished in 1928 after nearly a decade of work the structure was once derisively called the “Great Greek Garage,” though the temple-like design has since been nicknamed the Parthenon on the parkway by its supporters. Anybody who has seen the famous training montage in Rocky is already acquainted with the grand stairs leading up to the Greek Revival structure, but the building also contains numerous other striking details, including a pediment decorated in a polychrome sculpture called “Western Civilization.”

A four-story French mansion built in Manhattan for the scion of a rich Philadelphia family, the Drexel Mansion is one of a handful of Trumbauer commissions in New York City. The relatively sober 40-room structure was eventually split into a series of apartments after the Depression ended the era of grandiose estates, which housed celebs such as Ernest Hemingway and Joan Rivers, who spent a fortune on restoration, as shown in the adjacent photo.

Built in 1911 for Col. Robert Leaming Montgomery, the three-story, 38,000-square-foot, 50-room Georgian Revival home was the inspiration for The Philadelphia Story. It once sat upon an 800-acre estate, named after the family's ancestral home in Scotland, that contained dozens of buildings. Recently, a descendant of the family has announced plans to sell off part of the estate to developers.

Trumbauer designed this mansion on the famed Millionaire's Row for tobacco baron James B. Duke in 1909. Modeled after an 18th century Bordeaux hotel, the building, celebrated for its textured facade, was donated to the Institute of Fine Arts in 1952. The industrialist would remember Trumbauer when he later hired his firm to design buildings for the campus that was later named after him.