Pittsburg is a town in Coos County, New Hampshire, United States. The population was 867 at the 2000 census. It is the northernmost town in New Hampshire. U.S. Route 3 is the only major highway in the town.
Pittsburg derives its name from William Pitt, Prime Minister of England. Prior to its incorporation in 1840, the area was settled around 1810 and known as the Territory of Indian Stream. It had the unique distinction of having been its own micronation briefly during the 1830s, called the Republic of Indian Stream.
Pittsburg is the northernmost New Hampshire municipality. It shares an international border with Québec and borders the states of Maine and Vermont. The western edge of Pittsburg is defined by Halls Stream, being the "northwesternmost headwaters of the Connecticut River", which defined (ambiguously) the border in the Treaty of Paris of 1783.
Contained within the boundaries of Pittsburg are the Connecticut Lakes, which form the beginning of the Connecticut River. Pittsburg also contains the communities of Happy Corner, Idlewilde, and The Glen. Early maps (e.g. 1854) also show several grants that were incorporated into the eastern edge of Pittsburg, including Carlisle No. 1, Webster/Carlisle No. 2 and Hubbards No. 3, all north of Atkinson and Gilmanton Academy Grant. Sourced with thanks from En.wikipedia.org/wiki/Pittsburg,_New_Hampshire
Originally known as Indian Stream, Pittsburg is distinguished by having the largest amount of land area of any township. Covering the entire top of the state, the area includes Lake Francis, the three Connecticut Lakes, and the international boundary post erected on the 45th Parallel, halfway between the North Pole and the Equator. For a while, starting in 1832, Pittsburg was home to the Indian Stream Republic, a colony that established its own constitution and separate government. The Indian Stream Republic existed for over four years, then became a part of New Hampshire, and was incorporated with Pittsburg in 1840. The name Pittsburg is in honor of William Pitt, Prime Minister of England.
Sourced with thanks from Www.nhliving.com/towns/pittsburg/index.shtml