Originally from Minnesota, Dennis Kogl earned a bachelor's degree from Humboldt State College in California, and in the 1970s came to Alaska to work as a fisheries assistant at the University of Alaska Fairbanks (UAF). He went on to earn a master's degree in fisheries from UAF studying spawning salmon on the Chena River. He then became interested in wilderness living and mushing dogs, and with his wife, Sandy, moved to the Denali National Park area. They first homesteaded in the Yanert River valley, and in 1973 started Denali Dog Tours, thereby becoming one of the first to establish a dog mushing business to offer sled dog tours to visitors and transport supplies up to Denali for mountain climbing expeditions. Eventually, Dennis sold the business to Will Forsberg, and went to work for the National Park Service at Denali National Park. He has since retired, but continues to live near Denali National Park.