Derry is a town in Rockingham County, New Hampshire, United States. The population was 33,109 at the 2010 census, and an estimated 33,667 in 2018. Although it is a town and not a city, Derry is the fourth most populous community in the state. The town's nickname, "Spacetown", derives from the fact that Derry is the birthplace of Alan Shepard, the first astronaut from the United States in space. Derry was also for a time the home of the poet Robert Frost and his family.
The Derry census-designated place, with a 2010 population of 22,015, occupies the central part of the town, extending from the primary settlement of Derry in the west, centered on the intersection of New Hampshire Routes 28 and 102, to the town of Hampstead in the east. The town also includes the village of East Derry.
Although it was first settled by Scots-Irish families in 1719, Derry was not incorporated until 1827. It was originally a part of Londonderry, as were Windham and portions of Manchester, Salem and Hudson. The town was named after the city of Derry in Ireland, the Irish word Doire meaning "oak grove.” The first potato planted in the United States was sown in Derry in the town’s common field in 1719.