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Rockingham County, New Hampshire facts for kids

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Rockingham County
Aerial view of Portsmouth
Aerial view of Portsmouth
Map of New Hampshire highlighting Rockingham County
Location within the U.S. state of New Hampshire
Map of the United States highlighting New Hampshire
New Hampshire's location within the U.S.
Country  United States
State  New Hampshire
Founded 1769
Named for Charles Watson-Wentworth, 2nd Marquess of Rockingham
Seat Brentwood
Largest town Derry
 • Total 795.2 sq mi (2,060 km2)
 • Land 695.4 sq mi (1,801 km2)
 • Water 99.9 sq mi (259 km2)  12.6%
 • Total 314,176
 • Density 395.091/sq mi (152.545/km2)
Time zone UTC−5 (Eastern)
 • Summer (DST) UTC−4 (EDT)
Congressional districts 1st, 2nd

Rockingham County is a county in the U.S. state of New Hampshire. As of the 2020 census, the population was 314,176, making it New Hampshire's second-most populous county. The county seat is Brentwood. Rockingham County is part of the Boston-Cambridge-Newton, MA-NH Metropolitan Statistical Area and the greater Boston-Worcester-Providence, MA-RI-NH-CT Combined Statistical Area. Per the 2020 census, it was New Hampshire's fastest growing county from 2010 to 2020.[1]

As of 2014-2018 estimates from the American Community Survey, Rockingham County was the 4th wealthiest county in New England, with a median household income of $90,429.


The area that today is Rockingham County was first settled by Europeans moving north from the Plymouth Colony in Massachusetts as early as 1623. The government was linked tightly with Massachusetts until New Hampshire became a separate colony in 1679, but counties were not introduced until 1769.

Rockingham was identified in 1769 as one of five original counties for the colony. It is named for Charles Watson-Wentworth, 2nd Marquess of Rockingham, who had been Prime Minister in 1765-1766. The county was organized in 1771, with its county seat at Exeter. In 1844 its area was reduced by the formation of Belknap County to the northwest. In 1997 the county court facilities were moved to Brentwood, a rural town adjacent to Exeter.


According to the U.S. Census Bureau, the county has a total area of 795 square miles (2,060 km2), of which 695 square miles (1,800 km2) is land and 100 square miles (260 km2) (13%) is water. The highest point in Rockingham County is Nottingham Mountain, at 1,340 feet (410 m), in the town of Deerfield. The county contains the entirety of New Hampshire's Atlantic coast, which, at approximately 18 miles (29 km), is the shortest ocean coastline of any state in the nation.

Adjacent counties

National protected area

  • Great Bay National Wildlife Refuge


Historical population
Census Pop.
1790 43,184
1800 45,427 5.2%
1810 50,175 10.5%
1820 55,246 10.1%
1830 44,325 −19.8%
1840 45,771 3.3%
1850 49,194 7.5%
1860 50,122 1.9%
1870 47,297 −5.6%
1880 49,064 3.7%
1890 49,650 1.2%
1900 51,118 3.0%
1910 52,188 2.1%
1920 52,498 0.6%
1930 53,750 2.4%
1940 58,142 8.2%
1950 70,059 20.5%
1960 99,029 41.4%
1970 138,951 40.3%
1980 190,345 37.0%
1990 245,845 29.2%
2000 277,359 12.8%
2010 295,223 6.4%
2020 314,176 6.4%
U.S. Decennial Census
1790-1960 1900-1990
1990-2000 2010-2020

2010 census

As of the 2010 United States Census, there were 295,223 people, 115,033 households, and 79,832 families living in the county. The population density was 425.0 inhabitants per square mile (164.1/km2). There were 126,709 housing units at an average density of 182.4 per square mile (70.4/km2). The racial makeup of the county was 95.5% white, 1.7% Asian, 0.7% black or African American, 0.2% American Indian, 0.6% from other races, and 1.4% from two or more races. Those of Hispanic or Latino origin made up 2.1% of the population. In terms of ancestry, 26.9% were Irish, 19.0% were English, 14.8% were Italian, 9.7% were German, 7.3% were French Canadian, 5.6% were Polish, and 3.8% were American.

Of the 115,033 households, 32.9% had children under the age of 18 living with them, 56.4% were married couples living together, 8.9% had a female householder with no husband present, 30.6% were non-families, and 23.5% of all households were made up of individuals. The average household size was 2.54 and the average family size was 3.03. The median age was 42.2 years.

The median income for a household in the county was $75,825 and the median income for a family was $90,463. Males had a median income of $61,443 versus $42,478 for females. The per capita income for the county was $35,889. About 3.0% of families and 4.7% of the population were below the poverty line, including 4.9% of those under age 18 and 6.0% of those age 65 or over.


The Rockingham County Botanical Garden was a botanical garden located in Brentwood. Strawbery Banke Museum in Portsmouth is a collection of historic buildings from the seventeenth through nineteenth centuries. Canobie Lake Park, located in Salem, is an amusement park that opened in 1902. Also in Salem is Rockingham Park racetrack, which features weekly horse racing and is next to the Mall at Rockingham Park, and America's Stonehenge, which claims to be a pre-Columbian collection of stone structures. Derry was home to poet Robert Frost, who taught at nearby Pinkerton Academy. His home, the Robert Frost Farm, has been preserved as a state park.

Rockingham County is also home to New Hampshire's entire seacoast and features several popular resort towns. Hampton Beach has a boardwalk and Hampton Beach Casino Ballroom. The town of Rye features several undeveloped beaches such as Odiorne Point State Park and contains New Hampshire's portion of the Isles of Shoals. Seabrook contains the Seabrook Greyhound Racing Park and the Seabrook Nuclear Power Plant, the last nuclear plant opened in the United States.


Rockingham County SAU
Map of school administrative units in Rockingham County



Census-designated places


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