Premier Montana architects J. G. Link and C. S. Haire designed this three-story annex in 1906 as an extension of the elegant Thornton Hotel on Broadway. The building was one of the first designed by the two prestigious architects after they had formed their dynamic partnership in January of that year. A covered brick walkway connected the two buildings at the rear. Historic maps show that one of the five entries opened onto “sample rooms,” which spanned the back of the building. These allowed traveling salesmen a place to display their wares. There were also a business office, a store, and an assay office. The fifth entry gave access to the upper floors which, later converted into twenty-four apartments, originally accommodated hotel guests. Constructed at a cost of $20,000, the architectural features include brick pilasters separating the five entries, second-story windows framed in rusticated stone, and a decorative pressed metal cornice beneath a stepped parapet.