The floor plan of the main hotel (completed 1909) was laid out to accommodate the various activities popular with the American upper class at the turn of the twentieth century and the spaces are decorated accordingly. The music room, for instance, with its cream-colored walls (originally green and white), picture windows and fine, classical plaster-work was designed for letter-writing during the day and chamber music at night - cultured pursuits perceived as feminine. On the other hand, the smoking lounge (today the Piñon Room) and adjoining billiard room, with their dark stained-wood elements and granite arch fireplace were designated for enjoyment by male guests. Stanley himself, having been raised in a conservative household and having recovered from a serious lung disease, did not smoke cigars or drink alcohol, but these were essential after-dinner activities for most men at the time. Billiards, however, was among Stanley's most cherished pastimes. With no central heating or ventilation system, the structure was designed to facilitate natural airflow; the Palladian window at the top of the grand stair could be opened to induce a cross-breeze through the lobby, French doors in all the public spaces open onto verandas, and two curving staircases connecting the guest corridors prevent stagnant air in the upper floors. Although the main hotel is now heated in the winter, guests still depend on natural ventilation for cooling in the summer. Within a few years of opening, a hydraulic elevator was put in operation. In 1916, the east wing of the main building was extended in the rear adding several guest rooms. Around this time, the alcove of the music room was added. In 1921, a rear veranda was enclosed forming a room that currently serves as a gift shop. Around 1935, the hydraulic elevator system was replaced with a cable-operated system and extended to the fourth floor necessitating the addition of a secondary cupola to house the mechanical apparatus. Originally, a porte-cochere extended from the central bay of the front porch, but this was removed when the south terrace was converted into a parking lot. In 1983, a service tunnel was excavated, connecting the basement-level corridor to the staff entrance. It is cut directly through the living granite on which the hotel rests. The concert hall, east of the hotel, was built by Stanley in 1909 with the assistance of Henry "Lord Cornwallis" Rogers, the same architect who designed his summer cottage. According to popular legend, it was built by F.O. Stanley as a gift for his wife, Flora.