[1] After starting at the University of California, Berkeley, Kirker enlisted in the US Army during World War II.
[1] Like some other young men with Boy Scout hiking experience, he was recruited into the 10th Mountain Division where he trained alongside Charles Grier Sellers at the high-altitude Camp Hale in Colorado in 1943.
[4] Immediately after World War II, although he had not yet been awarded his Bachelor of Arts degree he attended Harvard and earned a Master of Business Administration degree, but returned to Europe as a civilian employee for the US Army (and engaged in many climbing trips in the Alps in his free time).
[3] Kirker returned to the University of California, Berkeley where he was awarded his Bachelor of Arts degree in 1951.
[3] He wrote his doctoral dissertation entitled "California Architecture in the Nineteenth Century: A Social History" under the direction of Professor Carl Bridenbaugh.