building was designed by Henry Janeway Hardenbergh in 1907, with a later addition, by Warren and Wetmore, being built from 1919 to 1922. The interiors of the main public spaces were primarily designed by Hardenbergh, Warren and Wetmore, and Schultze & Weaver. The other interior spaces were by Annabelle Selldorf and date largely to a renovation in 2008. Numerous contractors were involved in the construction of the hotel, including the Atlantic Terra Cotta Company and brick contractor Pfotenhauer & Nesbit. Facade The detail of the facade is concentrated on its two primary elevations, which face north toward Central Park and east toward Fifth Avenue. The facade's articulation consists of three horizontal sections similar to the components of a column, namely a base, shaft, and crown. The northern and eastern elevations are also split vertically into three portions, with the center portion being recessed. The northeastern and southeastern corners of the hotel contain rounded corners, which resemble turrets. There are numerous loggias, balustrades, columns, pilasters, balconies, and arches repeated across various parts of the facade. The 1921 annex contains a design that is largely similar to Hardenbergh's 1907 design. Base The first and second stories of the facade, respectively corresponding to the ground floor and floor 1 of the interior, are clad with rusticated blocks of marble. The third story, corresponding to floor 2 of the interior, contains a smooth marble surface. The hotel had two guest entrances in the 1907 design: the main entrance on Central Park South and a private entrance for long-term residents on 58th Street. The main entrance, in the center of the Central Park South facade, contains a porch above the three center bays, and large doorways. Since the hotel's 2008 renovation, the Central Park South entrance has served as the entrance to the building's condominiums. The Grand Army Plaza side originally contained a terrace called the Champagne Porch. There were three minor entrances, including one to the porch. The Champagne Porch was replaced by a large central entry in 1921. The entrance there consists of six Tuscan-style columns, supporting a balcony on the second story, immediately above ground level. The second and third stories at the center of the Grand Army Plaza facade contains paired Corinthian-style pilasters supporting an entablature. Upper stories The fourth through fifteenth stories, respectively corresponding to interior floors 3 through 14, are clad with white brick and typically contain rectangular windows.