There are several issues that are unique to high altitude. Altitude illnesses such as Acute Mountain Sickness, High Altitude Pulmonary Edema (HAPE) and High Altitude Cerebral Edema (HACE) can be deadly if not treated promptly and effectively. You can read more at our
Altitude Illness page.
Denali is possibly the coldest big mountain in the world. Being so close to the Arctic Circle, Denali will expose climbers to temperatures as cold as -20 to -40 degrees fahrenheit, in the summer. Please see our Hypothermia and Frostbite pages to learn more.