A very rich, lavish and heavily ornamented classical style favored by the Ecole des Beaux Arts in 19th century France. Very influential in the US in that many of the leading late 19th century architects had been trained at Ecole des Beaux Arts, e.g., Hunt, McKim, Richardson.

Broadly speaking, the term "Beaux Arts" refers to the American Renaissance period from about 1885 to the 1920s and encompasses the Italian Renaissance and Neoclassical Revivals. The style was interpreted in imposing row and freestanding town houses as well as grandiose country estates. Characteristically, these impressive residences featured facades of pristine white limestone or elegant buff-colored or yellow brick in a narrow gauge, often accented with enormous cartouches dripping with sculptural ornament.

Information provided by: http://ah.bfn.org