Monument is a city in Grant County, Oregon, United States. The population was 115 at the 2020 census. It is located near the confluence of the North and Middle Forks of the John Day River. Its post office was established in 1874 and named for a nearby mountain or rock formation.
As of 2000, the Monument School District, consisting of the Monument School, had a science building for its environmental sciences curriculum, which was paid for by a federal grant of about a $500,000. The program taught students about the ecology of local Ponderosa Pine forest and sagebrush steppe and the water quality and habitat of streams. The school had over 100 students in 1997, but the decline of ranching and timber production caused many families to move, bringing the number of children at the school down to 62 by the year 2000. Annual federal timber payments to the city of Monument declined from $100,000 in 1990 to $5,000 in 2000. With a population of 165 in 2000, Monument had "a grocery store, restaurant, tavern, three churches, a senior center, fire station and the offices of the Columbia Power Electric Cooperative utility."
Geography
According to the United States Census Bureau, the city has a total area of , all land. By road, Monument is southwest of Pendleton, about northwest of John Day, and about northeast of Bend.
Climate
This region experiences warm (but not hot) and dry summers, with no average monthly temperatures above . According to the Köppen Climate Classification system, Monument has a steppe climate, abbreviated "BSk" on climate maps. An average of about of precipitation falls on Monument each year.
Demographics
2020 census
As of the 2020 census, Monument had a population of 115. The median age was 48.8 years. 16.5% of residents were under the age of 18 and 28.7% of residents were 65 years of age or older. For every 100 females there were 113.0 males, and for every 100 females age 18 and over there were 128.6 males age 18 and over.
0% of residents lived in urban areas, while 100.0% lived in rural areas.
There were 67 households in Monument, of which 38.8% had children under the age of 18 living in them. Of all households, 31.3% were married-couple households, 32.8% were households with a male householder and no spouse or partner present, and 25.4% were households with a female householder and no spouse or partner present. About 38.8% of all households were made up of individuals and 20.9% had someone living alone who was 65 years of age or older.
! Race !! Number !! Percent
|-
| White || 99 || 86.1%
|-
| Black or African American || 0 || 0%
|-
| American Indian and Alaska Native || 0 || 0%
|-
| Asian || 0 || 0%
|-
| Native Hawaiian and Other Pacific Islander || 0 || 0%
|-
| Some other race || 5 || 4.3%
|-
| Two or more races || 11 || 9.6%
|-
| Hispanic or Latino (of any race) || 12 || 10.4%
|}
2010 census
As of the census of 2010, there were 128 people, 55 households, and 31 families residing in the city. The population density was . There were 82 housing units at an average density of . The racial makeup of the city was 94.5% White, 0.8% Native American, 3.9% from other races, and 0.8% from two or more races. Hispanic or Latino of any race were 3.9% of the population.
There were 55 households, of which 29.1% had children under the age of 18 living with them, 43.6% were married couples living together, 9.1% had a female householder with no husband present, 3.6% had a male householder with no wife present, and 43.6% were non-families. 38.2% of all households were made up of individuals, and 12.7% had someone living alone who was 65 years of age or older. The average household size was 2.33 and the average family size was 3.23.