Realizing the medical school had outgrown its facilities in Northwest Portland and recognizing the need for larger laboratories and better equipment, Mackenzie envisioned a new medical campus situated away from the heart of the city, one that would evolve into a world-class health center. During his tenure as dean of the UOMS, Mackenzie also served as chief surgeon of the Oregon-Washington Railroad & Navigation Company. In 1914, he used this connection to convince the company to donate a tract of unlikely property to the school. Originally purchased for the future construction of a rail switching station, the railway soon realized the steep topography of the 20 acre parcel on the top of Marquam Hill would make it an impractical location for such a task. Even though the property perched high on a tree-studded hill overlooking the city of Portland at first appeared to have little to offer as a campus setting, Mackenzie remarked, "...this tract would make an ideal University and Hospital center."

Accessible only by a steep winding road and far from Good Samaritan and St. Vincent Hospitals, Mackenzie's vision was called by many, "Mackenzie's Folly." The dean, however, remained dedicated to his vision and continued to campaign for the location despite his critics. In 1915, the legislature approved $50,000 for a building on the new campus and construction soon began in the tiny clearing on the top of the hill.