Marble House includes Marble House and many other historic Newport mansions, was added to the Register on December 8, 1972 and subsequently designated as a National Historic Landmark District on May 11, 1976. Marble House is one of the earliest examples of Beaux-Arts architecture in the United States, with design inspiration from the Petit Trianon at the Palace of Versailles. Jules Allard and Sons of Paris, first hired by the Vanderbilts to design some of the interiors for their Petit Chateau on Fifth Avenue in Manhattan, designed the French-inspired interiors of Marble House. The grounds were designed by landscape architect Ernest W.
Škvorec Chateau to this day. After the death of the Countess (1772), the chateau was no longer used as a mansion, but it fell to the mere seat of the economic administration of the estate, gradually dilapidated, while its parts were redesigned to flats for clerks and servants. Škvorec Chateau was still habitable in 1794, but in the years that followed it rapidly decayed. Instead of reconstruction, most of buildings were largely dismantled between 1860–84. The dilapidated north-western palace was demolished first, then the western two-storied wing was taken down in 1883. On the site of ruin of the old Gothic-Renaissance palace,