Olallie Butte is a steep-sided shield volcano

Shield volcano

A shield volcano is a type of volcano usually built almost entirely of fluid lava flows. They are named for their large size and low profile, resembling a warrior's shield. This is caused by the highly fluid lava they erupt, which travels farther than lava erupted from more explosive volcanoes...

 in the Cascade Range

Cascade Range

The Cascade Range is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as the North Cascades, and the notable volcanoes known as the High Cascades...

 of northern Oregon

Oregon

Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...

. It is the largest volcano and highest point in the 50 miles (80 km) distance between Mount Hood

Mount Hood

Mount Hood, called Wy'east by the Multnomah tribe, is a stratovolcano in the Cascade Volcanic Arc of northern Oregon. It was formed by a subduction zone and rests in the Pacific Northwest region of the United States...

 and Mount Jefferson

Mount Jefferson (Oregon)

Mount Jefferson is a stratovolcano in the Cascade Volcanic Arc, part of the Cascade Range, and is the second highest mountain in Oregon. Situated in the far northeastern corner of Linn County on the Jefferson County line, about east of Corvallis, Mount Jefferson is in a rugged wilderness and is...

, Oregon's two highest peaks. 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...

 glaciers carved two large cirques

Cirque (landform)

thumb|250 px|Two cirques with semi-permanent snowpatches in [[Abisko National Park]], [[Sweden]].A cirque or corrie is an amphitheatre-like valley head, formed at the head of a valley glacier by erosion...

 into the northeast and southeast flanks of the mountain exposing magma

Magma

Magma is a mixture of molten rock, volatiles and solids that is found beneath the surface of the Earth, and is expected to exist on other terrestrial planets. Besides molten rock, magma may also contain suspended crystals and dissolved gas and sometimes also gas bubbles. Magma often collects in...

 which hardened in the volcano's conduits to form the numerous spectacular rock pinnacles now found in the higher parts of the cirques.

A United States Forest Service

United States Forest Service

The United States Forest Service is an agency of the United States Department of Agriculture that administers the nation's 155 national forests and 20 national grasslands, which encompass...

 fire lookout tower

Fire lookout tower

A fire lookout tower, fire tower or lookout tower, provides housing and protection for a person known as a "fire lookout" whose duty it is to search for wildfires in the wilderness...

 was built on the summit in 1920, but abandoned in 1967. The collapsed timbers of the lookout tower still remain on the summit to this day. A wedge-shaped piece of land including the summit area which had been part of the Willamette National Forest

Willamette National Forest

The Willamette National Forest is a National Forest located in the central portion of the Cascade Range of US state of Oregon.It comprises 1,675,407 acres making it one of the largest national forests. Over 380,000 acres are designated wilderness which include seven major mountain peaks...

 was ceded to the Warm Springs Indian Reservation

Warm Springs Indian Reservation

The Warm Springs Indian Reservation consists of 1,019.385 sq mi in north central Oregon, in the United States, and is occupied and governed by the Confederated Tribes of Warm Springs.-Tribes:...

 under a revised interpretation of a 19th century treaty. Most of Olallie Butte except the lower western flank now lies within the reservation. Although official maintenance of the 4 miles (6.4 km) long trail to the summit also ended in the 1960s it still remains passable to hikers.

The summit of Olallie Butte is located on the border between Marion County

Marion County, Oregon

Marion County is a county located in the U.S. state of Oregon. It was originally named the Champooick District, after Champoeg, a meeting place on the Willamette River. On September 3, 1849, the territorial legislature renamed it in honor of Francis Marion, a Continental Army general of the...

 and Jefferson County

Jefferson County, Oregon

Jefferson County is a county located in the U.S. state of Oregon. In 2010, its population was 21,720. It is named after Mount Jefferson. The seat of the county is Madras.-History:...

. The highest point in Wasco County

Wasco County, Oregon

Wasco County is a county located in the U.S. state of Oregon. The county is named for a local tribe of Native Americans, the Wasco, a Chinook tribe who lived on the south side of the Columbia River. In 2010, its population was 25,213...

 is located at about 6280 foot in the northeast cirque. Olallie Butte overlooks the Olallie Scenic Area

Olallie Scenic Area

Olallie Scenic Area is a United States Forest Service designated scenic area located in Oregon’s Cascade Mountains. It is between Mount Hood on the north and Mount Jefferson to the south and contains Olallie Lake along with several smaller lakes...

 to the south which includes Olallie Lake. The term Olallie is Chinook Jargon

Chinook Jargon

Chinook Jargon originated as a pidgin trade language of the Pacific Northwest, and spread during the 19th century from the lower Columbia River, first to other areas in modern Oregon and Washington, then British Columbia and as far as Alaska, sometimes taking on characteristics of a creole language...

for berry which are abundant in the area.