Castle Green rose at the corner of Raymond Avenue and Green Street in 1898–99 as the Central Annex to the Hotel Green, Pasadena's premier social destination for industrialists, presidents, and Tournament of Roses visitors. Colonel George Gill Green, a Civil War veteran who built his fortune in patent medicines, had transformed the former Webster Hotel into the city's grandest hostelry, but by 1898 demand required expansion. The seven-story annex opened on January 16, 1899, connected to the original hotel across Raymond Avenue by an ornate enclosed pedestrian bridge. It was Pasadena's first fireproof building, constructed with a steel structure, brick walls, and concrete floors at a time when most of Southern California still built in wood.
Frederick Louis Roehrig designed the building as an exuberant fusion of Moorish Colonial, Spanish, and Victorian Revival styles, creating what the Los Angeles Times would later describe as "a fantastic folly created from the imagination of a Victorian architect with a penchant for Arabesque opulence." Cylindrical towers capped with domes anchor the Mediterranean Revival exterior, while balconies, verandahs, arches, and pillars animate the facades. The interior spaces embrace full Moorish Revival splendor, with original plaster moldings inspired by Islamic architecture of North Africa and Southwestern Europe, hand-carved fireplace mantles, decorative grills, and period lighting fixtures. The oldest wrought-iron man-operated elevator on the West Coast still operates within its walls.
