The 1877 Arnett-Fullen House is eligible for the National Register under Criterion C in the area of Architecture as an excellent example of the Mixed Style, incorporating elements of the Gothic Revival, Carpenter Gothic, Second Empire, and Italianate styles. While taking details from various styles is not unusual, the use of elements from four distinct styles is atypical. The Gothic Revival style is represent- ted by steeply pitched roofs, cross gables, and brick walls. The "gingerbread" bargeboards and elaborate scrolled and carved woodwork on the porches and gables are characteristic of Carpenter Gothic. The mansard tower, the dominant feature of the house, and the iron roof cresting are indicative of the Second Empire style. As was typical of the Second-Empire style, the house centers around this ornamental tower. Decorative brackets, narrow segmental arch windows and doors, and the canted bay window point to the Italianate influence. Taken all together, it is a masterful execution of Late Victorian architectural exuberance. The house was one of the early works of George E King, a prominent architect in the late 1800s, well known in Boulder and Leadville. At the time it was built, the house was considered the most architecturally beautiful house in the town of Boulder, and today retains a high level of architectural integrity.

The Arnett-Fullen House stands out as an example of how east-coast architectural styles influenced western settlers as they established communities in Colorado, melding local building materials with a whimsical design. The house reflects the economic aspirations of its owner, the growing economy of the area, and the Victorian middle-class ideals in the rough-and-tumble mining-supply town of then- rural Boulder. Today the small house continues to represent these traits, standing as a rare mix of Victorian aspirations, artistic precision, and entrepreneurial spirit, masterfully achieved within the limitations of the local resources of the young gold-rush town and its ambitious owner. Even the small size of the house reminds us that it was built early in the settlement of the West, when life was hard and resources were scarce.

Willamette Arnett built the house intending it as a showplace, despite the limited resources at his command. Though the house is not large, Arnett spent four thousand dollars building it, approximately twice the cost of the most expensive house in Boulder at that time. This price did not include the cast-iron fence, which came by rail from Pittsburgh to Omaha and by ox-cart from Omaha to Boulder at a cost of $1500. - NRHP, 24 November 2008