There are over 600,000 visitors (642,809 in 2017) that venture to Denali every year. At many national parks, there is an entrance station where visitors can be counted. But at Denali, visitors access the park in numerous ways and in many locations. Many arrive at the front entrance by car, train, or bus while others may travel into the park by plane or even dog team. Since there is no entrance station into the park it is difficult to estimate the number of visitors coming to the park each year. So how do social scientists estimate the total number of visitors to Denali? And how is park visitation different by month? Why do they use visits rather than visitors? How is a visit defined?