Perched dramatically on a basalt cliff 450 feet above the Spokane River, the Royal Riblet House-constructed in 1924-is an outstanding and highly idiosyncratic example of Florentine-style Italian Renaissance Revival architecture in Spokane County, Washington. Designed by prominent Spokane architect George H. Keith, the three-story mansion, historically known as "Cliff House," features a distinctive red-tile hip roof, stucco walls, and elegant arched windows designed to capture panoramic views of the Spokane Valley. The residence's design seamlessly integrates European elegance with the rugged, natural topography of the Inland Northwest, standing as a prominent regional landmark and a testament to the grand residential estates built during the area's early twentieth-century era of industrial expansion.

Historically, the property is significant for its direct association with Royal Newton Riblet, an eccentric inventor and executive with the internationally successful Riblet Tramway Company. Riblet utilized the estate as a personal laboratory and showcase for his technological innovations, integrating forward-thinking features such as an early automated lawn-sprinkler system, a master-clock system, and a private, five-passenger aerial tramway that crossed the river below. The surrounding estate grounds further reflect Riblet's creative vision, featuring a swimming pool carved directly out of the solid basalt cliff, a life-sized checkerboard, stone-walled terraced gardens, and a Florentine gatehouse. Now operating as the centerpiece of the Arbor Crest Wine Cellars, the estate retains its exceptional historic integrity and continues to illustrate the unique intersection of early industrial wealth, innovative engineering, and dramatic landscape design in Eastern Washington.