Denning is an isolated town in Ulster County, New York, USA. The population was 551 at the 2010 census. The town is named after an early landowner, William Denning. Denning is located in the western part of the county, deep inside the Catskill Mountains. The location of the town in the Catskill State Park accounts in part for its low population.
As of the census of 2000, there were 516 people, 215 households, and 124 families residing in the town. The population density was 4.9 people per square mile. There were 517 housing units at an average density of 4.9 per square mile. The racial makeup of the town was 95.93% White, 0.97% Native American, 0.19% Asian, and 2.91% from two or more races. Hispanic or Latino of any race were 1.55% of the population. There were 215 households out of which 18.1% had children under the age of 18 living with them, 49.8% were married couples living together, 6.0% had a female householder with no husband present, and 41.9% were non-families. 37.2% of all households were made up of individuals and 13.5% had someone living alone who was 65 years of age or older. The average household size was 2.25 and the average family size was 2.98. In the town, the population was spread out with 17.4% under the age of 18, 7.9% from 18 to 24, 28.5% from 25 to 44, 28.7% from 45 to 64, and 17.4% who were 65 years of age or older. The median age was 43 years. For every 100 females, there were 103.1 males. For every 100 females age 18 and over, there were 105.8 males. The median income for a household in the town was $40,893, and the median income for a family was $50,729. Males had a median income of $37,750 versus $25,179 for females. The per capita income for the town was $23,846. About 5.7% of families and 12.0% of the population were below the poverty line, including 9.3% of those under age 18 and 8.8% of those age 65 or over.
Communities and locations in Denning
Branch: A hamlet on CR 47, northeast of Frost Valley.
Bull Run: A hamlet north of Sundown on NY 42. Bull Run- name was changed to "Bullrun"- one word, then Re-named "Peekamose" in 1904 when Paul A. Sheeley was Postmaster
Denning: The hamlet of Denning is by the East Branch of the Neversink River.
Frost Valley: A hamlet on CR 47.
Greenville: A hamlet near the east town line on CR 46.
Ladleton: A hamlet by the East Branch of the Neversink River, southwest of Denning village.
Peekamose: A hamlet near the east town line on NY 42. Peekamose post office was formerly called "Bull Run" then "Bullrun" before changed to Peekamose in 1904.
Sundown: A hamlet near the south town line on CR 46.