Glacier Peak is the most isolated of the five major stratovolcano

Stratovolcano

A stratovolcano, also known as a composite volcano, is a tall, conical volcano built up by many layers of hardened lava, tephra, pumice, and volcanic ash. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile and periodic, explosive eruptions...

es (composite volcanoes) of the Cascade Volcanic Arc

Cascade Volcanoes

The Cascade Volcanoes are a number of volcanoes in a volcanic arc in western North America, extending from southwestern British Columbia through Washington and Oregon to Northern California, a distance of well over 700 mi ...

 in Washington. Located in the Glacier Peak Wilderness

Glacier Peak Wilderness

The Glacier Peak Wilderness, created by the US Forest Service in 1960 by efforts of the , four years before the 1964 wilderness legislation of the Congress, is located within portions of Chelan County, Snohomish County, and Skagit Counties in the North Cascades of Washington...

, the volcano is not easily discernible from any heavily populated area; as a result the volcano is largely understudied and not as much is known about it compared to other volcanoes in the area. Since the most recent ice age

Ice age

An ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers...

, it has produced some of largest and most explosive eruptions in the state.