Yamsay Mountain is a large shield volcano in the Cascade Range of south-central Oregon, located about 35 miles (56 km) east of Crater Lake on the border between Klamath County and Lake County. It is part of the Cascade Volcanic Arc located 30 to 50 miles (50 to 80 km) behind the main Cascade volcanic front. The best known members of this enigmatic arc are the massive shields of Newberry Volcano, about 55 miles (89 km) farther north in Oregon, and Medicine Lake Volcano, about 80 miles (130 km) south in northern California. Yamsay is the highest volcano in the eastern arc, almost 300 feet (90 m) higher than Newberry and Medicine Lake. A central part of Klamath mythology, the mountain offers activities such as hiking and horseback riding. The area near it has been inhabited by Native American tribes and settlers. Until the 1970s a fire lookout tower sat on the summit of the mountain, and its foundation remains to this day. Life in the Cascades is quite diverse. The western half of the range features lush vegetation, but the eastern portion is more dry. The range supports many animal species, including both endemic and endangered.