The AMK Ranch is a research center referred to as the University of Wyoming - National Park Research Station on the eastern shore of Jackson Lake in Grand Teton National Park. Also known as the Merymare, Lonetree and Mae-Lou Ranch, it was built beginning in the 1920s by William Louis Johnson, then expanded in the 1930s by Alfred Berol (Berolzheimer). Johnson built a lodge, barn and boathouse in 1927, while Berol added a larger lodge, new boathouse, and cabins, all in the rustic style.
The ranch is notable for the high level of craftsmanship and attention to detail, comparable to that seen in contemporary National Park Service structures. The Berol Lodge is the most extensively detailed rustic structure in Grand Teton.
William Johnson was an executive of The Hoover Company, who acquired the land in the 1920s and built a small lodge, garage and boathouse in 1927 using the log construction prevailing for dude ranches in Jackson Hole. Johnson died in 1931, and Berolzheimer, an officer of the Eagle (later Berol) Company, manufacturers of pencils, bought the ranch in 1936. Berol hired New York architect George W. Kosmak to design a new main lodge, boathouse, and cabins. Kosmak was assisted by Jackson architect Paul T. Colbron.
The AMK was listed on the National Register of Historic Places on April 23, 1990.