Rimrock is the sheer rock wall at the upper edge of a plateau

Plateau

In geology and earth science, a plateau , also called a high plain or tableland, is an area of highland, usually consisting of relatively flat terrain. A highly eroded plateau is called a dissected plateau...

, canyon

Canyon

A canyon or gorge is a deep ravine between cliffs often carved from the landscape by a river. Rivers have a natural tendency to reach a baseline elevation, which is the same elevation as the body of water it will eventually drain into. This forms a canyon. Most canyons were formed by a process of...

, or geological uplift. It may refer to either the rock formation or to the rock itself. Rimrock may be composed of almost any stone—basalt

Basalt

Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...

, gneiss

Gneiss

Gneiss is a common and widely distributed type of rock formed by high-grade regional metamorphic processes from pre-existing formations that were originally either igneous or sedimentary rocks.-Etymology:...

, granite

Granite

Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...

, sandstone

Sandstone

Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...

, etc.—and is frequently layered. Many times it overlays a softer stone which erodes away underneath. American Indians in the West often used cavities found below rimrock to construct dwellings and granaries.

Geographic placenames

The geologic formation has lent its name to many places in the western United States.

Communities:

• Rimrock, Arizona; Yavapai County, northeast of Camp Verde.
• Rimrock, California; San Bernardino County
  San Bernardino County, California
  San Bernardino County is a county in the U.S. state of California. As of the 2010 census, the population was 2,035,210, up from 1,709,434 as of the 2000 census...
  
  , east of San Bernardino
  San Bernardino, California
  San Bernardino is a city located in the Riverside-San Bernardino metropolitan area , and serves as the county seat of San Bernardino County, California, United States...
  
  .
• Rimrock, Montana; Yellowstone County
  Yellowstone County, Montana
  -National protected areas:* Nez Perce National Historical Park * Pompeys Pillar National Monument-Demographics:As of the census of 2000, there were 129,352 people, 52,084 households, and 34,219 families residing in the county. The population density was 49 people per square mile . There were...
  
  , west of Billings
  Billings, Montana
  Billings is the largest city in the U.S. state of Montana, and is the principal city of the Billings Metropolitan Area, the largest metropolitan area in over...
  
  .
• Rimrock, Washington; Yakima County
  Yakima County, Washington
  Yakima County is the second largest county by area in the U.S. state of Washington. It is named after the Yakama tribe of Native Americans. In the 2010 census, its population was 243,231...
  
  , near Rimrock Lake
  Rimrock Lake
  Rimrock Lake is a lake along the course of the Tieton River, in Yakima County, Washington state, USA.The lake is used as a storage reservoir for the Yakima Project, an irrigation project run by the United States Bureau of Reclamation. An impoundment of the Tieton River, Rimrock Lake's capacity and...
  
   on the Tieton River
  Tieton River
  The Tieton River is a tributary of the Naches River, in Yakima County, Washington in the United States.The Tieton River begins in two forks, the North Fork Tieton River and South Fork Tieton River. The North Fork originates at McCall Glacier on the eastern sides of Old Snowy Mountain, Ives Peak,...
  
   west of Yakima.
• Rim Rock Colony, Montana; Toole County
  Toole County, Montana
  -Demographics:As of the census of 2000, there were 5,267 people, 1,962 households, and 1,308 families residing in the county. The population density was 3 people per square mile . There were 2,300 housing units at an average density of 1 per square mile...
  
  , north of Helena
  Helena, Montana
  Helena is the capital city of the U.S. state of Montana and the county seat of Lewis and Clark County. The 2010 census put the population at 28,180. The local daily newspaper is the Independent Record. The Helena Brewers minor league baseball and Helena Bighorns minor league hockey team call the...
  
  .

Canyons:

• Rim Rock Canyon, Orange County, California
  Orange County, California
  Orange County is a county in the U.S. state of California. Its county seat is Santa Ana. As of the 2010 census, its population was 3,010,232, up from 2,846,293 at the 2000 census, making it the third most populous county in California, behind Los Angeles County and San Diego County...
  
  
• Rimrock Valley, Modoc County, California
  Modoc County, California
  Modoc County is a county located in the far northeast corner of the U.S. state of California, bounded by the state of Oregon to the north and the state of Nevada to the east. As of the 2010 census, its population was 9,686, up from 9,449 at the 2000 census. The current county seat is Alturas, the...
  
  
• Rimrock Gulch, Moffat County, Colorado
  Moffat County, Colorado
  Moffat County is the northwesternmost and the second most extensive of the 64 counties of the State of Colorado of the United States. The county population was 13,184 at U.S. Census 2000. The county seat is Craig.- History :...
  
  
• Rimrock Canyon, Nye County, Nevada
  Nye County, Nevada
  -National protected areas:* Ash Meadows National Wildlife Refuge* Death Valley National Park * Humboldt-Toiyabe National Forest * Spring Mountains National Recreation Area -Demographics:...
  
  
• Rim Rock Canyon, Lincoln County, New Mexico
  Lincoln County, New Mexico
  -2010:Whereas according to the 2010 U.S. Census Bureau:*85.1% White*0.5% Black*2.4% Native American*0.4% Asian*0.0% Native Hawaiian or Pacific Islander*2.5% Two or more races*9.1% Other races*29.8% Hispanic or Latino -2000:...
  
  
• Rimrock Draw, Washakie County, Wyoming
• Rim Rock Draw, Johnson Conty, Wyoming

Cliffs (unsurprisingly):

• Rimrocks, Yellowstone County, Montana
• Rimrock, El Paso County, Texas
• The Rimrocks, Kane County, Utah
  Kane County, Utah
  As of the census of 2000, there were 6,046 people, 2,237 households, and 1,628 families residing in the county. The population density was 2 people per square mile . There were 3,767 housing units at an average density of 1 per square mile...
  
  

Lakes:

• Rimrock Lake, Modoc County, California
• Rimrock Lake, Carbon County, Montana
  Carbon County, Montana
  -National protected areas:* Bighorn Canyon National Recreation Area * Custer National Forest * Gallatin National Forest -Economy:During the early history of Carbon County, coal mining was the predominant industry...
  
  
• Rimrock Lake, Colfax County, New Mexico
  Colfax County, New Mexico
  -2010:Whereas according to the 2010 U.S. Census Bureau:*83.8% White*0.5% Black*1.5% Native American*0.4% Asian*0.1% Native Hawaiian or Pacific Islander*3.6% Two or more races*10.1% Other races*47.2% Hispanic or Latino -2000:...
  
  
• Rimrock Lake, Marion County, Oregon
  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...
  
  
• Rimrock Lake
  Rimrock Lake
  Rimrock Lake is a lake along the course of the Tieton River, in Yakima County, Washington state, USA.The lake is used as a storage reservoir for the Yakima Project, an irrigation project run by the United States Bureau of Reclamation. An impoundment of the Tieton River, Rimrock Lake's capacity and...
  
  , Yakima County, Washington
  Yakima County, Washington
  Yakima County is the second largest county by area in the U.S. state of Washington. It is named after the Yakama tribe of Native Americans. In the 2010 census, its population was 243,231...
  
  
• Rimrock Lake, Teton County, Wyoming
  Teton County, Wyoming
  Teton County is a county located in the U.S. state of Wyoming. As of 2010, the population was 21,294. Its county seat is Jackson. Teton County contains the affluent Jackson Hole skiing area...
  
  

Mountains:

• Rimrock, Kootenai County, Idaho
  Kootenai County, Idaho
  Kootenai County is a county located in the U.S. state of Idaho. The county was established in 1864, named after Kootenai tribe. The entire county comprises the Coeur d'Alene, Idaho Metropolitan Statistical Area. The population was 138,494 at the 2010 census...
  
  
• Rimrock Butte, Glacier County, Montana
  Glacier County, Montana
  -National protected areas:* Glacier National Park * Lewis and Clark National Forest -Demographics:As of the census of 2000, there were 13,247 people, 4,304 households, and 3,245 families residing in the county. The population density was 4 people per square mile . There were 5,243 housing units...
  
  
• Rimrock Mountain, Hidalgo County, New Mexico
  Hidalgo County, New Mexico
  -2010:Whereas according to the 2010 U.S. Census Bureau:*85.3% White*0.6% Black*0.8% Native American*0.5% Asian*0.0% Native Hawaiian or Pacific Islander*1.8% Two or more races*11.0% Other races*56.6% Hispanic or Latino...
  
  

Ridges:

• Rim Rocks, Routt County, Colorado
  Routt County, Colorado
  Routt County is the 15th most extensive of the 64 counties of the state of Colorado of the United States. The county population was 19,690 at U.S. Census 2000. The county seat is Steamboat Springs.- History :...
  
  
• Rim Rock, Grant County, New Mexico
  Grant County, New Mexico
  -2010:Whereas according to the 2010 U.S. Census Bureau:*84.9% White*0.9% Black*1.4% Native American*0.4% Asian*0.1% Native Hawaiian or Pacific Islander*2.8% Two or more races*9.8% Other races*48.3% Hispanic or Latino -2000:...
  
  
• Rim Rock, Elko County, Nevada
  Elko County, Nevada
  -Demographics:As of the census of 2000, there were 45,291 people, 15,638 households, and 11,493 families residing in the county. The population density was 3/sq mi . There were 18,456 housing units at an average density of 1/sq mi...
  
  
• Rim Rock, Hood River County, Oregon
  Hood River County, Oregon
  -Demographics:As of the census of 2000, there were 20,411 people, 7,248 households, and 5,175 families residing in the county. The population density was 39 people per square mile . There were 7,818 housing units at an average density of 15 per square mile...
  
  

High Schools:

• Rimrock High School in Bruneau, Idaho
  Bruneau, Idaho
  Bruneau is an unincorporated community in Owyhee County in the southwestern part of the U.S. state of Idaho. Located at , the community sits at an altitude of 2549 feet ....